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small cleanup in CREDITS #12

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jankeromnes
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Hi,

Here is what I did to the CREDITS file:

  • I removed some tailing spaces
  • I verified the alphabetical order, and found 3 errors
  • I corrected them

Sorry for the microscopic commit.

Sincerely,
Jan.

@Gunni
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Gunni commented Sep 22, 2011

I believe pull requests like this are not used.

https://github.com/torvalds/linux/blob/master/Documentation/HOWTO

I recommend reading that.

@jankeromnes
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Thanks Gunni!

Now that I have read my way through the documentation, three small questions before I close this:

  • Should I send my (protocol appliant) email to [email protected]?
  • The CREDITS file seems to have no maintainers. Can I help by maintaining this file?
  • Should my email contain a patch, or can it be a link to my github clone?

@sc68cal
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sc68cal commented Sep 22, 2011

This is considered a trivial patch. Please consult MAINTAINERS and Documentation/SubmittingPatches for the person responsible and how to submit patches. Kernel.org is down right now, so [email protected] does not work. You can contact the current trivial patch maintainer at [email protected]

@Gunni
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Gunni commented Sep 22, 2011

Well, according to https://github.com/torvalds/linux/blob/master/Documentation/SubmittingPatches#L200 you should mail Jiri Kosina [email protected].

https://github.com/torvalds/linux/blob/master/MAINTAINERS#L6515

However since kernel.org is down i can not say where this should be sent, maybe use vger as a replacement and note that you're mailing there because the correct mail is down.

EDIT: yeah or use the mail sc68cal submitted: Jiri Kosina [email protected].

@jankeromnes
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Thanks a lot! I'll email my patch to Jiri Kosina.

@sc68cal
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sc68cal commented Sep 22, 2011

You also need to amend your commit message to add a sign off line. You need that in the commit message or your patch will not be accepted. Check the docs for more info

torvalds pushed a commit that referenced this pull request Nov 3, 2011
When the cgroup base was allocated with kmalloc, it was necessary to
annotate the variable with kmemleak_not_leak().  But because it has
recently been changed to be allocated with alloc_page() (which skips
kmemleak checks) causes a warning on boot up.

I was triggering this output:

 allocated 8388608 bytes of page_cgroup
 please try 'cgroup_disable=memory' option if you don't want memory cgroups
 kmemleak: Trying to color unknown object at 0xf5840000 as Grey
 Pid: 0, comm: swapper Not tainted 3.0.0-test #12
 Call Trace:
  [<c17e34e6>] ? printk+0x1d/0x1f^M
  [<c10e2941>] paint_ptr+0x4f/0x78
  [<c178ab57>] kmemleak_not_leak+0x58/0x7d
  [<c108ae9f>] ? __rcu_read_unlock+0x9/0x7d
  [<c1cdb462>] kmemleak_init+0x19d/0x1e9
  [<c1cbf771>] start_kernel+0x346/0x3ec
  [<c1cbf1b4>] ? loglevel+0x18/0x18
  [<c1cbf0aa>] i386_start_kernel+0xaa/0xb0

After a bit of debugging I tracked the object 0xf840000 (and others) down
to the cgroup code.  The change from allocating base with kmalloc to
alloc_page() has the base not calling kmemleak_alloc() which adds the
pointer to the object_tree_root, but kmemleak_not_leak() adds it to the
crt_early_log[] table.  On kmemleak_init(), the entry is found in the
early_log[] but not the object_tree_root, and this error message is
displayed.

If alloc_page() fails then it defaults back to vmalloc() which still uses
the kmemleak_alloc() which makes us still need the kmemleak_not_leak()
call.  The solution is to call the kmemleak_alloc() directly if the
alloc_page() succeeds.

Reviewed-by: Michal Hocko <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>
Acked-by: Catalin Marinas <[email protected]>
Signed-off-by: Jonathan Nieder <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
cuviper pushed a commit to cuviper/linux-uprobes that referenced this pull request Nov 3, 2011
* Ingo Molnar <[email protected]> wrote:

> The patch below addresses these concerns, serializes the output, tidies up the
> printout, resulting in this new output:

There's one bug remaining that my patch does not address: the vCPUs are not
printed in order:

# vCPU #0's dump:
# vCPU #2's dump:
# vCPU torvalds#24's dump:
# vCPU #5's dump:
# vCPU torvalds#39's dump:
# vCPU torvalds#38's dump:
# vCPU torvalds#51's dump:
# vCPU torvalds#11's dump:
# vCPU torvalds#10's dump:
# vCPU torvalds#12's dump:

This is undesirable as the order of printout is highly random, so successive
dumps are difficult to compare.

The patch below serializes the signalling itself. (this is on top of the
previous patch)

The patch also tweaks the vCPU printout line a bit so that it does not start
with '#', which is discarded if such messages are pasted into Git commit
messages.

Signed-off-by: Ingo Molnar <[email protected]>
Signed-off-by: Pekka Enberg <[email protected]>
torvalds pushed a commit that referenced this pull request Dec 15, 2011
If the pte mapping in generic_perform_write() is unmapped between
iov_iter_fault_in_readable() and iov_iter_copy_from_user_atomic(), the
"copied" parameter to ->end_write can be zero. ext4 couldn't cope with
it with delayed allocations enabled. This skips the i_disksize
enlargement logic if copied is zero and no new data was appeneded to
the inode.

 gdb> bt
 #0  0xffffffff811afe80 in ext4_da_should_update_i_disksize (file=0xffff88003f606a80, mapping=0xffff88001d3824e0, pos=0x1\
 08000, len=0x1000, copied=0x0, page=0xffffea0000d792e8, fsdata=0x0) at fs/ext4/inode.c:2467
 #1  ext4_da_write_end (file=0xffff88003f606a80, mapping=0xffff88001d3824e0, pos=0x108000, len=0x1000, copied=0x0, page=0\
 xffffea0000d792e8, fsdata=0x0) at fs/ext4/inode.c:2512
 #2  0xffffffff810d97f1 in generic_perform_write (iocb=<value optimized out>, iov=<value optimized out>, nr_segs=<value o\
 ptimized out>, pos=0x108000, ppos=0xffff88001e26be40, count=<value optimized out>, written=0x0) at mm/filemap.c:2440
 #3  generic_file_buffered_write (iocb=<value optimized out>, iov=<value optimized out>, nr_segs=<value optimized out>, p\
 os=0x108000, ppos=0xffff88001e26be40, count=<value optimized out>, written=0x0) at mm/filemap.c:2482
 #4  0xffffffff810db5d1 in __generic_file_aio_write (iocb=0xffff88001e26bde8, iov=0xffff88001e26bec8, nr_segs=0x1, ppos=0\
 xffff88001e26be40) at mm/filemap.c:2600
 #5  0xffffffff810db853 in generic_file_aio_write (iocb=0xffff88001e26bde8, iov=0xffff88001e26bec8, nr_segs=<value optimi\
 zed out>, pos=<value optimized out>) at mm/filemap.c:2632
 #6  0xffffffff811a71aa in ext4_file_write (iocb=0xffff88001e26bde8, iov=0xffff88001e26bec8, nr_segs=0x1, pos=0x108000) a\
 t fs/ext4/file.c:136
 #7  0xffffffff811375aa in do_sync_write (filp=0xffff88003f606a80, buf=<value optimized out>, len=<value optimized out>, \
 ppos=0xffff88001e26bf48) at fs/read_write.c:406
 #8  0xffffffff81137e56 in vfs_write (file=0xffff88003f606a80, buf=0x1ec2960 <Address 0x1ec2960 out of bounds>, count=0x4\
 000, pos=0xffff88001e26bf48) at fs/read_write.c:435
 #9  0xffffffff8113816c in sys_write (fd=<value optimized out>, buf=0x1ec2960 <Address 0x1ec2960 out of bounds>, count=0x\
 4000) at fs/read_write.c:487
 #10 <signal handler called>
 #11 0x00007f120077a390 in __brk_reservation_fn_dmi_alloc__ ()
 #12 0x0000000000000000 in ?? ()
 gdb> print offset
 $22 = 0xffffffffffffffff
 gdb> print idx
 $23 = 0xffffffff
 gdb> print inode->i_blkbits
 $24 = 0xc
 gdb> up
 #1  ext4_da_write_end (file=0xffff88003f606a80, mapping=0xffff88001d3824e0, pos=0x108000, len=0x1000, copied=0x0, page=0\
 xffffea0000d792e8, fsdata=0x0) at fs/ext4/inode.c:2512
 2512                    if (ext4_da_should_update_i_disksize(page, end)) {
 gdb> print start
 $25 = 0x0
 gdb> print end
 $26 = 0xffffffffffffffff
 gdb> print pos
 $27 = 0x108000
 gdb> print new_i_size
 $28 = 0x108000
 gdb> print ((struct ext4_inode_info *)((char *)inode-((int)(&((struct ext4_inode_info *)0)->vfs_inode))))->i_disksize
 $29 = 0xd9000
 gdb> down
 2467            for (i = 0; i < idx; i++)
 gdb> print i
 $30 = 0xd44acbee

This is 100% reproducible with some autonuma development code tuned in
a very aggressive manner (not normal way even for knumad) which does
"exotic" changes to the ptes. It wouldn't normally trigger but I don't
see why it can't happen normally if the page is added to swap cache in
between the two faults leading to "copied" being zero (which then
hangs in ext4). So it should be fixed. Especially possible with lumpy
reclaim (albeit disabled if compaction is enabled) as that would
ignore the young bits in the ptes.

Signed-off-by: Andrea Arcangeli <[email protected]>
Signed-off-by: "Theodore Ts'o" <[email protected]>
Cc: [email protected]
torvalds pushed a commit that referenced this pull request Feb 8, 2012
Overly indented code should be refactored.

Suggest refactoring excessive indentation of of
if/else/for/do/while/switch statements.

For example:

$ cat t.c
#include <stdio.h>
#include <stdlib.h>

int main(int argc, char **argv)
{

	if (1)
		if (2)
			if (3)
				if (4)
					if (5)
						if (6)
							if (7)
								if (8)
									;
	return 0;
}

$ ./scripts/checkpatch.pl -f t.c
WARNING: Too many leading tabs - consider code refactoring
#12: FILE: t.c:12:
+						if (6)

WARNING: Too many leading tabs - consider code refactoring
#13: FILE: t.c:13:
+							if (7)

WARNING: Too many leading tabs - consider code refactoring
#14: FILE: t.c:14:
+								if (8)

total: 0 errors, 3 warnings, 17 lines checked

t.c has style problems, please review.

If any of these errors are false positives, please report
them to the maintainer, see CHECKPATCH in MAINTAINERS.

Signed-off-by: Joe Perches <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
jkstrick pushed a commit to jkstrick/linux that referenced this pull request Feb 11, 2012
If the netdev is already in NETREG_UNREGISTERING/_UNREGISTERED state, do not
update the real num tx queues. netdev_queue_update_kobjects() is already
called via remove_queue_kobjects() at NETREG_UNREGISTERING time. So, when
upper layer driver, e.g., FCoE protocol stack is monitoring the netdev
event of NETDEV_UNREGISTER and calls back to LLD ndo_fcoe_disable() to remove
extra queues allocated for FCoE, the associated txq sysfs kobjects are already
removed, and trying to update the real num queues would cause something like
below:

...
PID: 25138  TASK: ffff88021e64c440  CPU: 3   COMMAND: "kworker/3:3"
 #0 [ffff88021f007760] machine_kexec at ffffffff810226d9
 #1 [ffff88021f0077d0] crash_kexec at ffffffff81089d2d
 #2 [ffff88021f0078a0] oops_end at ffffffff813bca78
 #3 [ffff88021f0078d0] no_context at ffffffff81029e72
 #4 [ffff88021f007920] __bad_area_nosemaphore at ffffffff8102a155
 #5 [ffff88021f0079f0] bad_area_nosemaphore at ffffffff8102a23e
 torvalds#6 [ffff88021f007a00] do_page_fault at ffffffff813bf32e
 torvalds#7 [ffff88021f007b10] page_fault at ffffffff813bc045
    [exception RIP: sysfs_find_dirent+17]
    RIP: ffffffff81178611  RSP: ffff88021f007bc0  RFLAGS: 00010246
    RAX: ffff88021e64c440  RBX: ffffffff8156cc63  RCX: 0000000000000004
    RDX: ffffffff8156cc63  RSI: 0000000000000000  RDI: 0000000000000000
    RBP: ffff88021f007be0   R8: 0000000000000004   R9: 0000000000000008
    R10: ffffffff816fed00  R11: 0000000000000004  R12: 0000000000000000
    R13: ffffffff8156cc63  R14: 0000000000000000  R15: ffff8802222a0000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 torvalds#8 [ffff88021f007be8] sysfs_get_dirent at ffffffff81178c07
 torvalds#9 [ffff88021f007c18] sysfs_remove_group at ffffffff8117ac27
torvalds#10 [ffff88021f007c48] netdev_queue_update_kobjects at ffffffff813178f9
torvalds#11 [ffff88021f007c88] netif_set_real_num_tx_queues at ffffffff81303e38
torvalds#12 [ffff88021f007cc8] ixgbe_set_num_queues at ffffffffa0249763 [ixgbe]
torvalds#13 [ffff88021f007cf8] ixgbe_init_interrupt_scheme at ffffffffa024ea89 [ixgbe]
torvalds#14 [ffff88021f007d48] ixgbe_fcoe_disable at ffffffffa0267113 [ixgbe]
torvalds#15 [ffff88021f007d68] vlan_dev_fcoe_disable at ffffffffa014fef5 [8021q]
torvalds#16 [ffff88021f007d78] fcoe_interface_cleanup at ffffffffa02b7dfd [fcoe]
torvalds#17 [ffff88021f007df8] fcoe_destroy_work at ffffffffa02b7f08 [fcoe]
torvalds#18 [ffff88021f007e18] process_one_work at ffffffff8105d7ca
torvalds#19 [ffff88021f007e68] worker_thread at ffffffff81060513
torvalds#20 [ffff88021f007ee8] kthread at ffffffff810648b6
torvalds#21 [ffff88021f007f48] kernel_thread_helper at ffffffff813c40f4

Signed-off-by: Yi Zou <[email protected]>
Tested-by: Ross Brattain <[email protected]>
Tested-by: Stephen Ko <[email protected]>
Signed-off-by: Jeff Kirsher <[email protected]>
zachariasmaladroit pushed a commit to galaxys-cm7miui-kernel/linux that referenced this pull request Feb 11, 2012
If the netdev is already in NETREG_UNREGISTERING/_UNREGISTERED state, do not
update the real num tx queues. netdev_queue_update_kobjects() is already
called via remove_queue_kobjects() at NETREG_UNREGISTERING time. So, when
upper layer driver, e.g., FCoE protocol stack is monitoring the netdev
event of NETDEV_UNREGISTER and calls back to LLD ndo_fcoe_disable() to remove
extra queues allocated for FCoE, the associated txq sysfs kobjects are already
removed, and trying to update the real num queues would cause something like
below:

...
PID: 25138  TASK: ffff88021e64c440  CPU: 3   COMMAND: "kworker/3:3"
 #0 [ffff88021f007760] machine_kexec at ffffffff810226d9
 #1 [ffff88021f0077d0] crash_kexec at ffffffff81089d2d
 #2 [ffff88021f0078a0] oops_end at ffffffff813bca78
 #3 [ffff88021f0078d0] no_context at ffffffff81029e72
 #4 [ffff88021f007920] __bad_area_nosemaphore at ffffffff8102a155
 #5 [ffff88021f0079f0] bad_area_nosemaphore at ffffffff8102a23e
 torvalds#6 [ffff88021f007a00] do_page_fault at ffffffff813bf32e
 torvalds#7 [ffff88021f007b10] page_fault at ffffffff813bc045
    [exception RIP: sysfs_find_dirent+17]
    RIP: ffffffff81178611  RSP: ffff88021f007bc0  RFLAGS: 00010246
    RAX: ffff88021e64c440  RBX: ffffffff8156cc63  RCX: 0000000000000004
    RDX: ffffffff8156cc63  RSI: 0000000000000000  RDI: 0000000000000000
    RBP: ffff88021f007be0   R8: 0000000000000004   R9: 0000000000000008
    R10: ffffffff816fed00  R11: 0000000000000004  R12: 0000000000000000
    R13: ffffffff8156cc63  R14: 0000000000000000  R15: ffff8802222a0000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 torvalds#8 [ffff88021f007be8] sysfs_get_dirent at ffffffff81178c07
 torvalds#9 [ffff88021f007c18] sysfs_remove_group at ffffffff8117ac27
torvalds#10 [ffff88021f007c48] netdev_queue_update_kobjects at ffffffff813178f9
torvalds#11 [ffff88021f007c88] netif_set_real_num_tx_queues at ffffffff81303e38
torvalds#12 [ffff88021f007cc8] ixgbe_set_num_queues at ffffffffa0249763 [ixgbe]
torvalds#13 [ffff88021f007cf8] ixgbe_init_interrupt_scheme at ffffffffa024ea89 [ixgbe]
torvalds#14 [ffff88021f007d48] ixgbe_fcoe_disable at ffffffffa0267113 [ixgbe]
torvalds#15 [ffff88021f007d68] vlan_dev_fcoe_disable at ffffffffa014fef5 [8021q]
torvalds#16 [ffff88021f007d78] fcoe_interface_cleanup at ffffffffa02b7dfd [fcoe]
torvalds#17 [ffff88021f007df8] fcoe_destroy_work at ffffffffa02b7f08 [fcoe]
torvalds#18 [ffff88021f007e18] process_one_work at ffffffff8105d7ca
torvalds#19 [ffff88021f007e68] worker_thread at ffffffff81060513
torvalds#20 [ffff88021f007ee8] kthread at ffffffff810648b6
torvalds#21 [ffff88021f007f48] kernel_thread_helper at ffffffff813c40f4

Signed-off-by: Yi Zou <[email protected]>
Tested-by: Ross Brattain <[email protected]>
Tested-by: Stephen Ko <[email protected]>
Signed-off-by: Jeff Kirsher <[email protected]>
tworaz pushed a commit to tworaz/linux that referenced this pull request Feb 13, 2012
…S block during isolation for migration

commit 0bf380b upstream.

When isolating for migration, migration starts at the start of a zone
which is not necessarily pageblock aligned.  Further, it stops isolating
when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally
not aligned.  This allows isolate_migratepages() to call pfn_to_page() on
an invalid PFN which can result in a crash.  This was originally reported
against a 3.0-based kernel with the following trace in a crash dump.

PID: 9902   TASK: d47aecd0  CPU: 0   COMMAND: "memcg_process_s"
 #0 [d72d3ad0] crash_kexec at c028cfdb
 #1 [d72d3b24] oops_end at c05c5322
 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60
 #3 [d72d3bec] bad_area at c0227fb6
 #4 [d72d3c00] do_page_fault at c05c72ec
 #5 [d72d3c80] error_code (via page_fault) at c05c47a4
    EAX: 00000000  EBX: 000c0000  ECX: 00000001  EDX: 00000807  EBP: 000c0000
    DS:  007b      ESI: 00000001  ES:  007b      EDI: f3000a80  GS:  6f50
    CS:  0060      EIP: c030b15a  ERR: ffffffff  EFLAGS: 00010002
 torvalds#6 [d72d3cb4] isolate_migratepages at c030b15a
 torvalds#7 [d72d3d1] zone_watermark_ok at c02d26cb
 torvalds#8 [d72d3d2c] compact_zone at c030b8de
 torvalds#9 [d72d3d68] compact_zone_order at c030bba1
torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84
torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7
torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7
torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97
torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845
torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb
torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6
torvalds#17 [d72d3f30] do_page_fault at c05c70ed
torvalds#18 [d72d3fb0] error_code (via page_fault) at c05c47a4
    EAX: b71ff000  EBX: 00000001  ECX: 00001600  EDX: 00000431
    DS:  007b      ESI: 08048950  ES:  007b      EDI: bfaa3788
    SS:  007b      ESP: bfaa36e0  EBP: bfaa3828  GS:  6f50
    CS:  0073      EIP: 080487c8  ERR: ffffffff  EFLAGS: 00010202

It was also reported by Herbert van den Bergh against 3.1-based kernel
with the following snippet from the console log.

BUG: unable to handle kernel paging request at 01c00008
IP: [<c0522399>] isolate_migratepages+0x119/0x390
*pdpt = 000000002f7ce001 *pde = 0000000000000000

It is expected that it also affects 3.2.x and current mainline.

The problem is that pfn_valid is only called on the first PFN being
checked and that PFN is not necessarily aligned.  Lets say we have a case
like this

H = MAX_ORDER_NR_PAGES boundary
| = pageblock boundary
m = cc->migrate_pfn
f = cc->free_pfn
o = memory hole

H------|------H------|----m-Hoooooo|ooooooH-f----|------H

The migrate_pfn is just below a memory hole and the free scanner is beyond
the hole.  When isolate_migratepages started, it scans from migrate_pfn to
migrate_pfn+pageblock_nr_pages which is now in a memory hole.  It checks
pfn_valid() on the first PFN but then scans into the hole where there are
not necessarily valid struct pages.

This patch ensures that isolate_migratepages calls pfn_valid when
necessary.

Reported-by: Herbert van den Bergh <[email protected]>
Tested-by: Herbert van den Bergh <[email protected]>
Signed-off-by: Mel Gorman <[email protected]>
Acked-by: Michal Nazarewicz <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
xXorAa pushed a commit to xXorAa/linux that referenced this pull request Feb 17, 2012
…S block during isolation for migration

commit 0bf380b upstream.

When isolating for migration, migration starts at the start of a zone
which is not necessarily pageblock aligned.  Further, it stops isolating
when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally
not aligned.  This allows isolate_migratepages() to call pfn_to_page() on
an invalid PFN which can result in a crash.  This was originally reported
against a 3.0-based kernel with the following trace in a crash dump.

PID: 9902   TASK: d47aecd0  CPU: 0   COMMAND: "memcg_process_s"
 #0 [d72d3ad0] crash_kexec at c028cfdb
 #1 [d72d3b24] oops_end at c05c5322
 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60
 #3 [d72d3bec] bad_area at c0227fb6
 #4 [d72d3c00] do_page_fault at c05c72ec
 #5 [d72d3c80] error_code (via page_fault) at c05c47a4
    EAX: 00000000  EBX: 000c0000  ECX: 00000001  EDX: 00000807  EBP: 000c0000
    DS:  007b      ESI: 00000001  ES:  007b      EDI: f3000a80  GS:  6f50
    CS:  0060      EIP: c030b15a  ERR: ffffffff  EFLAGS: 00010002
 torvalds#6 [d72d3cb4] isolate_migratepages at c030b15a
 torvalds#7 [d72d3d1] zone_watermark_ok at c02d26cb
 torvalds#8 [d72d3d2c] compact_zone at c030b8de
 torvalds#9 [d72d3d68] compact_zone_order at c030bba1
torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84
torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7
torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7
torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97
torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845
torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb
torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6
torvalds#17 [d72d3f30] do_page_fault at c05c70ed
torvalds#18 [d72d3fb0] error_code (via page_fault) at c05c47a4
    EAX: b71ff000  EBX: 00000001  ECX: 00001600  EDX: 00000431
    DS:  007b      ESI: 08048950  ES:  007b      EDI: bfaa3788
    SS:  007b      ESP: bfaa36e0  EBP: bfaa3828  GS:  6f50
    CS:  0073      EIP: 080487c8  ERR: ffffffff  EFLAGS: 00010202

It was also reported by Herbert van den Bergh against 3.1-based kernel
with the following snippet from the console log.

BUG: unable to handle kernel paging request at 01c00008
IP: [<c0522399>] isolate_migratepages+0x119/0x390
*pdpt = 000000002f7ce001 *pde = 0000000000000000

It is expected that it also affects 3.2.x and current mainline.

The problem is that pfn_valid is only called on the first PFN being
checked and that PFN is not necessarily aligned.  Lets say we have a case
like this

H = MAX_ORDER_NR_PAGES boundary
| = pageblock boundary
m = cc->migrate_pfn
f = cc->free_pfn
o = memory hole

H------|------H------|----m-Hoooooo|ooooooH-f----|------H

The migrate_pfn is just below a memory hole and the free scanner is beyond
the hole.  When isolate_migratepages started, it scans from migrate_pfn to
migrate_pfn+pageblock_nr_pages which is now in a memory hole.  It checks
pfn_valid() on the first PFN but then scans into the hole where there are
not necessarily valid struct pages.

This patch ensures that isolate_migratepages calls pfn_valid when
necessary.

Reported-by: Herbert van den Bergh <[email protected]>
Tested-by: Herbert van den Bergh <[email protected]>
Signed-off-by: Mel Gorman <[email protected]>
Acked-by: Michal Nazarewicz <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
koenkooi pushed a commit to koenkooi/linux that referenced this pull request Feb 23, 2012
…S block during isolation for migration

commit 0bf380b upstream.

When isolating for migration, migration starts at the start of a zone
which is not necessarily pageblock aligned.  Further, it stops isolating
when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally
not aligned.  This allows isolate_migratepages() to call pfn_to_page() on
an invalid PFN which can result in a crash.  This was originally reported
against a 3.0-based kernel with the following trace in a crash dump.

PID: 9902   TASK: d47aecd0  CPU: 0   COMMAND: "memcg_process_s"
 #0 [d72d3ad0] crash_kexec at c028cfdb
 #1 [d72d3b24] oops_end at c05c5322
 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60
 #3 [d72d3bec] bad_area at c0227fb6
 #4 [d72d3c00] do_page_fault at c05c72ec
 #5 [d72d3c80] error_code (via page_fault) at c05c47a4
    EAX: 00000000  EBX: 000c0000  ECX: 00000001  EDX: 00000807  EBP: 000c0000
    DS:  007b      ESI: 00000001  ES:  007b      EDI: f3000a80  GS:  6f50
    CS:  0060      EIP: c030b15a  ERR: ffffffff  EFLAGS: 00010002
 #6 [d72d3cb4] isolate_migratepages at c030b15a
 #7 [d72d3d1] zone_watermark_ok at c02d26cb
 #8 [d72d3d2c] compact_zone at c030b8de
 #9 [d72d3d68] compact_zone_order at c030bba1
torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84
torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7
torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7
torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97
torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845
torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb
torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6
torvalds#17 [d72d3f30] do_page_fault at c05c70ed
torvalds#18 [d72d3fb0] error_code (via page_fault) at c05c47a4
    EAX: b71ff000  EBX: 00000001  ECX: 00001600  EDX: 00000431
    DS:  007b      ESI: 08048950  ES:  007b      EDI: bfaa3788
    SS:  007b      ESP: bfaa36e0  EBP: bfaa3828  GS:  6f50
    CS:  0073      EIP: 080487c8  ERR: ffffffff  EFLAGS: 00010202

It was also reported by Herbert van den Bergh against 3.1-based kernel
with the following snippet from the console log.

BUG: unable to handle kernel paging request at 01c00008
IP: [<c0522399>] isolate_migratepages+0x119/0x390
*pdpt = 000000002f7ce001 *pde = 0000000000000000

It is expected that it also affects 3.2.x and current mainline.

The problem is that pfn_valid is only called on the first PFN being
checked and that PFN is not necessarily aligned.  Lets say we have a case
like this

H = MAX_ORDER_NR_PAGES boundary
| = pageblock boundary
m = cc->migrate_pfn
f = cc->free_pfn
o = memory hole

H------|------H------|----m-Hoooooo|ooooooH-f----|------H

The migrate_pfn is just below a memory hole and the free scanner is beyond
the hole.  When isolate_migratepages started, it scans from migrate_pfn to
migrate_pfn+pageblock_nr_pages which is now in a memory hole.  It checks
pfn_valid() on the first PFN but then scans into the hole where there are
not necessarily valid struct pages.

This patch ensures that isolate_migratepages calls pfn_valid when
necessary.

Reported-by: Herbert van den Bergh <[email protected]>
Tested-by: Herbert van den Bergh <[email protected]>
Signed-off-by: Mel Gorman <[email protected]>
Acked-by: Michal Nazarewicz <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
koenkooi pushed a commit to koenkooi/linux that referenced this pull request Mar 1, 2012
…S block during isolation for migration

commit 0bf380b upstream.

When isolating for migration, migration starts at the start of a zone
which is not necessarily pageblock aligned.  Further, it stops isolating
when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally
not aligned.  This allows isolate_migratepages() to call pfn_to_page() on
an invalid PFN which can result in a crash.  This was originally reported
against a 3.0-based kernel with the following trace in a crash dump.

PID: 9902   TASK: d47aecd0  CPU: 0   COMMAND: "memcg_process_s"
 #0 [d72d3ad0] crash_kexec at c028cfdb
 #1 [d72d3b24] oops_end at c05c5322
 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60
 #3 [d72d3bec] bad_area at c0227fb6
 #4 [d72d3c00] do_page_fault at c05c72ec
 #5 [d72d3c80] error_code (via page_fault) at c05c47a4
    EAX: 00000000  EBX: 000c0000  ECX: 00000001  EDX: 00000807  EBP: 000c0000
    DS:  007b      ESI: 00000001  ES:  007b      EDI: f3000a80  GS:  6f50
    CS:  0060      EIP: c030b15a  ERR: ffffffff  EFLAGS: 00010002
 #6 [d72d3cb4] isolate_migratepages at c030b15a
 #7 [d72d3d1] zone_watermark_ok at c02d26cb
 #8 [d72d3d2c] compact_zone at c030b8de
 #9 [d72d3d68] compact_zone_order at c030bba1
torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84
torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7
torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7
torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97
torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845
torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb
torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6
torvalds#17 [d72d3f30] do_page_fault at c05c70ed
torvalds#18 [d72d3fb0] error_code (via page_fault) at c05c47a4
    EAX: b71ff000  EBX: 00000001  ECX: 00001600  EDX: 00000431
    DS:  007b      ESI: 08048950  ES:  007b      EDI: bfaa3788
    SS:  007b      ESP: bfaa36e0  EBP: bfaa3828  GS:  6f50
    CS:  0073      EIP: 080487c8  ERR: ffffffff  EFLAGS: 00010202

It was also reported by Herbert van den Bergh against 3.1-based kernel
with the following snippet from the console log.

BUG: unable to handle kernel paging request at 01c00008
IP: [<c0522399>] isolate_migratepages+0x119/0x390
*pdpt = 000000002f7ce001 *pde = 0000000000000000

It is expected that it also affects 3.2.x and current mainline.

The problem is that pfn_valid is only called on the first PFN being
checked and that PFN is not necessarily aligned.  Lets say we have a case
like this

H = MAX_ORDER_NR_PAGES boundary
| = pageblock boundary
m = cc->migrate_pfn
f = cc->free_pfn
o = memory hole

H------|------H------|----m-Hoooooo|ooooooH-f----|------H

The migrate_pfn is just below a memory hole and the free scanner is beyond
the hole.  When isolate_migratepages started, it scans from migrate_pfn to
migrate_pfn+pageblock_nr_pages which is now in a memory hole.  It checks
pfn_valid() on the first PFN but then scans into the hole where there are
not necessarily valid struct pages.

This patch ensures that isolate_migratepages calls pfn_valid when
necessary.

Reported-by: Herbert van den Bergh <[email protected]>
Tested-by: Herbert van den Bergh <[email protected]>
Signed-off-by: Mel Gorman <[email protected]>
Acked-by: Michal Nazarewicz <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
koenkooi pushed a commit to koenkooi/linux that referenced this pull request Mar 19, 2012
…S block during isolation for migration

commit 0bf380b upstream.

When isolating for migration, migration starts at the start of a zone
which is not necessarily pageblock aligned.  Further, it stops isolating
when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally
not aligned.  This allows isolate_migratepages() to call pfn_to_page() on
an invalid PFN which can result in a crash.  This was originally reported
against a 3.0-based kernel with the following trace in a crash dump.

PID: 9902   TASK: d47aecd0  CPU: 0   COMMAND: "memcg_process_s"
 #0 [d72d3ad0] crash_kexec at c028cfdb
 #1 [d72d3b24] oops_end at c05c5322
 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60
 #3 [d72d3bec] bad_area at c0227fb6
 #4 [d72d3c00] do_page_fault at c05c72ec
 #5 [d72d3c80] error_code (via page_fault) at c05c47a4
    EAX: 00000000  EBX: 000c0000  ECX: 00000001  EDX: 00000807  EBP: 000c0000
    DS:  007b      ESI: 00000001  ES:  007b      EDI: f3000a80  GS:  6f50
    CS:  0060      EIP: c030b15a  ERR: ffffffff  EFLAGS: 00010002
 #6 [d72d3cb4] isolate_migratepages at c030b15a
 #7 [d72d3d1] zone_watermark_ok at c02d26cb
 #8 [d72d3d2c] compact_zone at c030b8de
 #9 [d72d3d68] compact_zone_order at c030bba1
torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84
torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7
torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7
torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97
torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845
torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb
torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6
torvalds#17 [d72d3f30] do_page_fault at c05c70ed
torvalds#18 [d72d3fb0] error_code (via page_fault) at c05c47a4
    EAX: b71ff000  EBX: 00000001  ECX: 00001600  EDX: 00000431
    DS:  007b      ESI: 08048950  ES:  007b      EDI: bfaa3788
    SS:  007b      ESP: bfaa36e0  EBP: bfaa3828  GS:  6f50
    CS:  0073      EIP: 080487c8  ERR: ffffffff  EFLAGS: 00010202

It was also reported by Herbert van den Bergh against 3.1-based kernel
with the following snippet from the console log.

BUG: unable to handle kernel paging request at 01c00008
IP: [<c0522399>] isolate_migratepages+0x119/0x390
*pdpt = 000000002f7ce001 *pde = 0000000000000000

It is expected that it also affects 3.2.x and current mainline.

The problem is that pfn_valid is only called on the first PFN being
checked and that PFN is not necessarily aligned.  Lets say we have a case
like this

H = MAX_ORDER_NR_PAGES boundary
| = pageblock boundary
m = cc->migrate_pfn
f = cc->free_pfn
o = memory hole

H------|------H------|----m-Hoooooo|ooooooH-f----|------H

The migrate_pfn is just below a memory hole and the free scanner is beyond
the hole.  When isolate_migratepages started, it scans from migrate_pfn to
migrate_pfn+pageblock_nr_pages which is now in a memory hole.  It checks
pfn_valid() on the first PFN but then scans into the hole where there are
not necessarily valid struct pages.

This patch ensures that isolate_migratepages calls pfn_valid when
necessary.

Reported-by: Herbert van den Bergh <[email protected]>
Tested-by: Herbert van den Bergh <[email protected]>
Signed-off-by: Mel Gorman <[email protected]>
Acked-by: Michal Nazarewicz <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
koenkooi pushed a commit to koenkooi/linux that referenced this pull request Mar 22, 2012
…S block during isolation for migration

commit 0bf380b upstream.

When isolating for migration, migration starts at the start of a zone
which is not necessarily pageblock aligned.  Further, it stops isolating
when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally
not aligned.  This allows isolate_migratepages() to call pfn_to_page() on
an invalid PFN which can result in a crash.  This was originally reported
against a 3.0-based kernel with the following trace in a crash dump.

PID: 9902   TASK: d47aecd0  CPU: 0   COMMAND: "memcg_process_s"
 #0 [d72d3ad0] crash_kexec at c028cfdb
 #1 [d72d3b24] oops_end at c05c5322
 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60
 #3 [d72d3bec] bad_area at c0227fb6
 #4 [d72d3c00] do_page_fault at c05c72ec
 #5 [d72d3c80] error_code (via page_fault) at c05c47a4
    EAX: 00000000  EBX: 000c0000  ECX: 00000001  EDX: 00000807  EBP: 000c0000
    DS:  007b      ESI: 00000001  ES:  007b      EDI: f3000a80  GS:  6f50
    CS:  0060      EIP: c030b15a  ERR: ffffffff  EFLAGS: 00010002
 #6 [d72d3cb4] isolate_migratepages at c030b15a
 #7 [d72d3d1] zone_watermark_ok at c02d26cb
 #8 [d72d3d2c] compact_zone at c030b8de
 #9 [d72d3d68] compact_zone_order at c030bba1
torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84
torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7
torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7
torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97
torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845
torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb
torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6
torvalds#17 [d72d3f30] do_page_fault at c05c70ed
torvalds#18 [d72d3fb0] error_code (via page_fault) at c05c47a4
    EAX: b71ff000  EBX: 00000001  ECX: 00001600  EDX: 00000431
    DS:  007b      ESI: 08048950  ES:  007b      EDI: bfaa3788
    SS:  007b      ESP: bfaa36e0  EBP: bfaa3828  GS:  6f50
    CS:  0073      EIP: 080487c8  ERR: ffffffff  EFLAGS: 00010202

It was also reported by Herbert van den Bergh against 3.1-based kernel
with the following snippet from the console log.

BUG: unable to handle kernel paging request at 01c00008
IP: [<c0522399>] isolate_migratepages+0x119/0x390
*pdpt = 000000002f7ce001 *pde = 0000000000000000

It is expected that it also affects 3.2.x and current mainline.

The problem is that pfn_valid is only called on the first PFN being
checked and that PFN is not necessarily aligned.  Lets say we have a case
like this

H = MAX_ORDER_NR_PAGES boundary
| = pageblock boundary
m = cc->migrate_pfn
f = cc->free_pfn
o = memory hole

H------|------H------|----m-Hoooooo|ooooooH-f----|------H

The migrate_pfn is just below a memory hole and the free scanner is beyond
the hole.  When isolate_migratepages started, it scans from migrate_pfn to
migrate_pfn+pageblock_nr_pages which is now in a memory hole.  It checks
pfn_valid() on the first PFN but then scans into the hole where there are
not necessarily valid struct pages.

This patch ensures that isolate_migratepages calls pfn_valid when
necessary.

Reported-by: Herbert van den Bergh <[email protected]>
Tested-by: Herbert van den Bergh <[email protected]>
Signed-off-by: Mel Gorman <[email protected]>
Acked-by: Michal Nazarewicz <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
koenkooi pushed a commit to koenkooi/linux that referenced this pull request Apr 2, 2012
…S block during isolation for migration

commit 0bf380b upstream.

When isolating for migration, migration starts at the start of a zone
which is not necessarily pageblock aligned.  Further, it stops isolating
when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally
not aligned.  This allows isolate_migratepages() to call pfn_to_page() on
an invalid PFN which can result in a crash.  This was originally reported
against a 3.0-based kernel with the following trace in a crash dump.

PID: 9902   TASK: d47aecd0  CPU: 0   COMMAND: "memcg_process_s"
 #0 [d72d3ad0] crash_kexec at c028cfdb
 #1 [d72d3b24] oops_end at c05c5322
 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60
 #3 [d72d3bec] bad_area at c0227fb6
 #4 [d72d3c00] do_page_fault at c05c72ec
 #5 [d72d3c80] error_code (via page_fault) at c05c47a4
    EAX: 00000000  EBX: 000c0000  ECX: 00000001  EDX: 00000807  EBP: 000c0000
    DS:  007b      ESI: 00000001  ES:  007b      EDI: f3000a80  GS:  6f50
    CS:  0060      EIP: c030b15a  ERR: ffffffff  EFLAGS: 00010002
 #6 [d72d3cb4] isolate_migratepages at c030b15a
 #7 [d72d3d1] zone_watermark_ok at c02d26cb
 #8 [d72d3d2c] compact_zone at c030b8de
 #9 [d72d3d68] compact_zone_order at c030bba1
torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84
torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7
torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7
torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97
torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845
torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb
torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6
torvalds#17 [d72d3f30] do_page_fault at c05c70ed
torvalds#18 [d72d3fb0] error_code (via page_fault) at c05c47a4
    EAX: b71ff000  EBX: 00000001  ECX: 00001600  EDX: 00000431
    DS:  007b      ESI: 08048950  ES:  007b      EDI: bfaa3788
    SS:  007b      ESP: bfaa36e0  EBP: bfaa3828  GS:  6f50
    CS:  0073      EIP: 080487c8  ERR: ffffffff  EFLAGS: 00010202

It was also reported by Herbert van den Bergh against 3.1-based kernel
with the following snippet from the console log.

BUG: unable to handle kernel paging request at 01c00008
IP: [<c0522399>] isolate_migratepages+0x119/0x390
*pdpt = 000000002f7ce001 *pde = 0000000000000000

It is expected that it also affects 3.2.x and current mainline.

The problem is that pfn_valid is only called on the first PFN being
checked and that PFN is not necessarily aligned.  Lets say we have a case
like this

H = MAX_ORDER_NR_PAGES boundary
| = pageblock boundary
m = cc->migrate_pfn
f = cc->free_pfn
o = memory hole

H------|------H------|----m-Hoooooo|ooooooH-f----|------H

The migrate_pfn is just below a memory hole and the free scanner is beyond
the hole.  When isolate_migratepages started, it scans from migrate_pfn to
migrate_pfn+pageblock_nr_pages which is now in a memory hole.  It checks
pfn_valid() on the first PFN but then scans into the hole where there are
not necessarily valid struct pages.

This patch ensures that isolate_migratepages calls pfn_valid when
necessary.

Reported-by: Herbert van den Bergh <[email protected]>
Tested-by: Herbert van den Bergh <[email protected]>
Signed-off-by: Mel Gorman <[email protected]>
Acked-by: Michal Nazarewicz <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
koenkooi pushed a commit to koenkooi/linux that referenced this pull request Apr 9, 2012
…S block during isolation for migration

commit 0bf380b upstream.

When isolating for migration, migration starts at the start of a zone
which is not necessarily pageblock aligned.  Further, it stops isolating
when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally
not aligned.  This allows isolate_migratepages() to call pfn_to_page() on
an invalid PFN which can result in a crash.  This was originally reported
against a 3.0-based kernel with the following trace in a crash dump.

PID: 9902   TASK: d47aecd0  CPU: 0   COMMAND: "memcg_process_s"
 #0 [d72d3ad0] crash_kexec at c028cfdb
 #1 [d72d3b24] oops_end at c05c5322
 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60
 #3 [d72d3bec] bad_area at c0227fb6
 #4 [d72d3c00] do_page_fault at c05c72ec
 #5 [d72d3c80] error_code (via page_fault) at c05c47a4
    EAX: 00000000  EBX: 000c0000  ECX: 00000001  EDX: 00000807  EBP: 000c0000
    DS:  007b      ESI: 00000001  ES:  007b      EDI: f3000a80  GS:  6f50
    CS:  0060      EIP: c030b15a  ERR: ffffffff  EFLAGS: 00010002
 #6 [d72d3cb4] isolate_migratepages at c030b15a
 #7 [d72d3d1] zone_watermark_ok at c02d26cb
 #8 [d72d3d2c] compact_zone at c030b8de
 #9 [d72d3d68] compact_zone_order at c030bba1
torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84
torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7
torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7
torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97
torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845
torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb
torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6
torvalds#17 [d72d3f30] do_page_fault at c05c70ed
torvalds#18 [d72d3fb0] error_code (via page_fault) at c05c47a4
    EAX: b71ff000  EBX: 00000001  ECX: 00001600  EDX: 00000431
    DS:  007b      ESI: 08048950  ES:  007b      EDI: bfaa3788
    SS:  007b      ESP: bfaa36e0  EBP: bfaa3828  GS:  6f50
    CS:  0073      EIP: 080487c8  ERR: ffffffff  EFLAGS: 00010202

It was also reported by Herbert van den Bergh against 3.1-based kernel
with the following snippet from the console log.

BUG: unable to handle kernel paging request at 01c00008
IP: [<c0522399>] isolate_migratepages+0x119/0x390
*pdpt = 000000002f7ce001 *pde = 0000000000000000

It is expected that it also affects 3.2.x and current mainline.

The problem is that pfn_valid is only called on the first PFN being
checked and that PFN is not necessarily aligned.  Lets say we have a case
like this

H = MAX_ORDER_NR_PAGES boundary
| = pageblock boundary
m = cc->migrate_pfn
f = cc->free_pfn
o = memory hole

H------|------H------|----m-Hoooooo|ooooooH-f----|------H

The migrate_pfn is just below a memory hole and the free scanner is beyond
the hole.  When isolate_migratepages started, it scans from migrate_pfn to
migrate_pfn+pageblock_nr_pages which is now in a memory hole.  It checks
pfn_valid() on the first PFN but then scans into the hole where there are
not necessarily valid struct pages.

This patch ensures that isolate_migratepages calls pfn_valid when
necessary.

Reported-by: Herbert van den Bergh <[email protected]>
Tested-by: Herbert van den Bergh <[email protected]>
Signed-off-by: Mel Gorman <[email protected]>
Acked-by: Michal Nazarewicz <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
koenkooi pushed a commit to koenkooi/linux that referenced this pull request Apr 11, 2012
…S block during isolation for migration

commit 0bf380b upstream.

When isolating for migration, migration starts at the start of a zone
which is not necessarily pageblock aligned.  Further, it stops isolating
when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally
not aligned.  This allows isolate_migratepages() to call pfn_to_page() on
an invalid PFN which can result in a crash.  This was originally reported
against a 3.0-based kernel with the following trace in a crash dump.

PID: 9902   TASK: d47aecd0  CPU: 0   COMMAND: "memcg_process_s"
 #0 [d72d3ad0] crash_kexec at c028cfdb
 #1 [d72d3b24] oops_end at c05c5322
 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60
 #3 [d72d3bec] bad_area at c0227fb6
 #4 [d72d3c00] do_page_fault at c05c72ec
 #5 [d72d3c80] error_code (via page_fault) at c05c47a4
    EAX: 00000000  EBX: 000c0000  ECX: 00000001  EDX: 00000807  EBP: 000c0000
    DS:  007b      ESI: 00000001  ES:  007b      EDI: f3000a80  GS:  6f50
    CS:  0060      EIP: c030b15a  ERR: ffffffff  EFLAGS: 00010002
 #6 [d72d3cb4] isolate_migratepages at c030b15a
 #7 [d72d3d1] zone_watermark_ok at c02d26cb
 #8 [d72d3d2c] compact_zone at c030b8de
 #9 [d72d3d68] compact_zone_order at c030bba1
torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84
torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7
torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7
torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97
torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845
torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb
torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6
torvalds#17 [d72d3f30] do_page_fault at c05c70ed
torvalds#18 [d72d3fb0] error_code (via page_fault) at c05c47a4
    EAX: b71ff000  EBX: 00000001  ECX: 00001600  EDX: 00000431
    DS:  007b      ESI: 08048950  ES:  007b      EDI: bfaa3788
    SS:  007b      ESP: bfaa36e0  EBP: bfaa3828  GS:  6f50
    CS:  0073      EIP: 080487c8  ERR: ffffffff  EFLAGS: 00010202

It was also reported by Herbert van den Bergh against 3.1-based kernel
with the following snippet from the console log.

BUG: unable to handle kernel paging request at 01c00008
IP: [<c0522399>] isolate_migratepages+0x119/0x390
*pdpt = 000000002f7ce001 *pde = 0000000000000000

It is expected that it also affects 3.2.x and current mainline.

The problem is that pfn_valid is only called on the first PFN being
checked and that PFN is not necessarily aligned.  Lets say we have a case
like this

H = MAX_ORDER_NR_PAGES boundary
| = pageblock boundary
m = cc->migrate_pfn
f = cc->free_pfn
o = memory hole

H------|------H------|----m-Hoooooo|ooooooH-f----|------H

The migrate_pfn is just below a memory hole and the free scanner is beyond
the hole.  When isolate_migratepages started, it scans from migrate_pfn to
migrate_pfn+pageblock_nr_pages which is now in a memory hole.  It checks
pfn_valid() on the first PFN but then scans into the hole where there are
not necessarily valid struct pages.

This patch ensures that isolate_migratepages calls pfn_valid when
necessary.

Reported-by: Herbert van den Bergh <[email protected]>
Tested-by: Herbert van den Bergh <[email protected]>
Signed-off-by: Mel Gorman <[email protected]>
Acked-by: Michal Nazarewicz <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
koenkooi pushed a commit to koenkooi/linux that referenced this pull request Apr 12, 2012
…S block during isolation for migration

commit 0bf380b upstream.

When isolating for migration, migration starts at the start of a zone
which is not necessarily pageblock aligned.  Further, it stops isolating
when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally
not aligned.  This allows isolate_migratepages() to call pfn_to_page() on
an invalid PFN which can result in a crash.  This was originally reported
against a 3.0-based kernel with the following trace in a crash dump.

PID: 9902   TASK: d47aecd0  CPU: 0   COMMAND: "memcg_process_s"
 #0 [d72d3ad0] crash_kexec at c028cfdb
 #1 [d72d3b24] oops_end at c05c5322
 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60
 #3 [d72d3bec] bad_area at c0227fb6
 #4 [d72d3c00] do_page_fault at c05c72ec
 #5 [d72d3c80] error_code (via page_fault) at c05c47a4
    EAX: 00000000  EBX: 000c0000  ECX: 00000001  EDX: 00000807  EBP: 000c0000
    DS:  007b      ESI: 00000001  ES:  007b      EDI: f3000a80  GS:  6f50
    CS:  0060      EIP: c030b15a  ERR: ffffffff  EFLAGS: 00010002
 #6 [d72d3cb4] isolate_migratepages at c030b15a
 #7 [d72d3d1] zone_watermark_ok at c02d26cb
 #8 [d72d3d2c] compact_zone at c030b8de
 #9 [d72d3d68] compact_zone_order at c030bba1
torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84
torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7
torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7
torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97
torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845
torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb
torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6
torvalds#17 [d72d3f30] do_page_fault at c05c70ed
torvalds#18 [d72d3fb0] error_code (via page_fault) at c05c47a4
    EAX: b71ff000  EBX: 00000001  ECX: 00001600  EDX: 00000431
    DS:  007b      ESI: 08048950  ES:  007b      EDI: bfaa3788
    SS:  007b      ESP: bfaa36e0  EBP: bfaa3828  GS:  6f50
    CS:  0073      EIP: 080487c8  ERR: ffffffff  EFLAGS: 00010202

It was also reported by Herbert van den Bergh against 3.1-based kernel
with the following snippet from the console log.

BUG: unable to handle kernel paging request at 01c00008
IP: [<c0522399>] isolate_migratepages+0x119/0x390
*pdpt = 000000002f7ce001 *pde = 0000000000000000

It is expected that it also affects 3.2.x and current mainline.

The problem is that pfn_valid is only called on the first PFN being
checked and that PFN is not necessarily aligned.  Lets say we have a case
like this

H = MAX_ORDER_NR_PAGES boundary
| = pageblock boundary
m = cc->migrate_pfn
f = cc->free_pfn
o = memory hole

H------|------H------|----m-Hoooooo|ooooooH-f----|------H

The migrate_pfn is just below a memory hole and the free scanner is beyond
the hole.  When isolate_migratepages started, it scans from migrate_pfn to
migrate_pfn+pageblock_nr_pages which is now in a memory hole.  It checks
pfn_valid() on the first PFN but then scans into the hole where there are
not necessarily valid struct pages.

This patch ensures that isolate_migratepages calls pfn_valid when
necessary.

Reported-by: Herbert van den Bergh <[email protected]>
Tested-by: Herbert van den Bergh <[email protected]>
Signed-off-by: Mel Gorman <[email protected]>
Acked-by: Michal Nazarewicz <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
psanford pushed a commit to retailnext/linux that referenced this pull request Apr 16, 2012
BugLink: http://bugs.launchpad.net/bugs/907778

commit ea51d13 upstream.

If the pte mapping in generic_perform_write() is unmapped between
iov_iter_fault_in_readable() and iov_iter_copy_from_user_atomic(), the
"copied" parameter to ->end_write can be zero. ext4 couldn't cope with
it with delayed allocations enabled. This skips the i_disksize
enlargement logic if copied is zero and no new data was appeneded to
the inode.

 gdb> bt
 #0  0xffffffff811afe80 in ext4_da_should_update_i_disksize (file=0xffff88003f606a80, mapping=0xffff88001d3824e0, pos=0x1\
 08000, len=0x1000, copied=0x0, page=0xffffea0000d792e8, fsdata=0x0) at fs/ext4/inode.c:2467
 #1  ext4_da_write_end (file=0xffff88003f606a80, mapping=0xffff88001d3824e0, pos=0x108000, len=0x1000, copied=0x0, page=0\
 xffffea0000d792e8, fsdata=0x0) at fs/ext4/inode.c:2512
 #2  0xffffffff810d97f1 in generic_perform_write (iocb=<value optimized out>, iov=<value optimized out>, nr_segs=<value o\
 ptimized out>, pos=0x108000, ppos=0xffff88001e26be40, count=<value optimized out>, written=0x0) at mm/filemap.c:2440
 #3  generic_file_buffered_write (iocb=<value optimized out>, iov=<value optimized out>, nr_segs=<value optimized out>, p\
 os=0x108000, ppos=0xffff88001e26be40, count=<value optimized out>, written=0x0) at mm/filemap.c:2482
 #4  0xffffffff810db5d1 in __generic_file_aio_write (iocb=0xffff88001e26bde8, iov=0xffff88001e26bec8, nr_segs=0x1, ppos=0\
 xffff88001e26be40) at mm/filemap.c:2600
 #5  0xffffffff810db853 in generic_file_aio_write (iocb=0xffff88001e26bde8, iov=0xffff88001e26bec8, nr_segs=<value optimi\
 zed out>, pos=<value optimized out>) at mm/filemap.c:2632
 torvalds#6  0xffffffff811a71aa in ext4_file_write (iocb=0xffff88001e26bde8, iov=0xffff88001e26bec8, nr_segs=0x1, pos=0x108000) a\
 t fs/ext4/file.c:136
 torvalds#7  0xffffffff811375aa in do_sync_write (filp=0xffff88003f606a80, buf=<value optimized out>, len=<value optimized out>, \
 ppos=0xffff88001e26bf48) at fs/read_write.c:406
 torvalds#8  0xffffffff81137e56 in vfs_write (file=0xffff88003f606a80, buf=0x1ec2960 <Address 0x1ec2960 out of bounds>, count=0x4\
 000, pos=0xffff88001e26bf48) at fs/read_write.c:435
 torvalds#9  0xffffffff8113816c in sys_write (fd=<value optimized out>, buf=0x1ec2960 <Address 0x1ec2960 out of bounds>, count=0x\
 4000) at fs/read_write.c:487
 torvalds#10 <signal handler called>
 torvalds#11 0x00007f120077a390 in __brk_reservation_fn_dmi_alloc__ ()
 torvalds#12 0x0000000000000000 in ?? ()
 gdb> print offset
 $22 = 0xffffffffffffffff
 gdb> print idx
 $23 = 0xffffffff
 gdb> print inode->i_blkbits
 $24 = 0xc
 gdb> up
 #1  ext4_da_write_end (file=0xffff88003f606a80, mapping=0xffff88001d3824e0, pos=0x108000, len=0x1000, copied=0x0, page=0\
 xffffea0000d792e8, fsdata=0x0) at fs/ext4/inode.c:2512
 2512                    if (ext4_da_should_update_i_disksize(page, end)) {
 gdb> print start
 $25 = 0x0
 gdb> print end
 $26 = 0xffffffffffffffff
 gdb> print pos
 $27 = 0x108000
 gdb> print new_i_size
 $28 = 0x108000
 gdb> print ((struct ext4_inode_info *)((char *)inode-((int)(&((struct ext4_inode_info *)0)->vfs_inode))))->i_disksize
 $29 = 0xd9000
 gdb> down
 2467            for (i = 0; i < idx; i++)
 gdb> print i
 $30 = 0xd44acbee

This is 100% reproducible with some autonuma development code tuned in
a very aggressive manner (not normal way even for knumad) which does
"exotic" changes to the ptes. It wouldn't normally trigger but I don't
see why it can't happen normally if the page is added to swap cache in
between the two faults leading to "copied" being zero (which then
hangs in ext4). So it should be fixed. Especially possible with lumpy
reclaim (albeit disabled if compaction is enabled) as that would
ignore the young bits in the ptes.

Signed-off-by: Andrea Arcangeli <[email protected]>
Signed-off-by: "Theodore Ts'o" <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Tim Gardner <[email protected]>
Signed-off-by: Brad Figg <[email protected]>
psanford pushed a commit to retailnext/linux that referenced this pull request Apr 16, 2012
…S block during isolation for migration

BugLink: http://bugs.launchpad.net/bugs/931719

commit 0bf380b upstream.

When isolating for migration, migration starts at the start of a zone
which is not necessarily pageblock aligned.  Further, it stops isolating
when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally
not aligned.  This allows isolate_migratepages() to call pfn_to_page() on
an invalid PFN which can result in a crash.  This was originally reported
against a 3.0-based kernel with the following trace in a crash dump.

PID: 9902   TASK: d47aecd0  CPU: 0   COMMAND: "memcg_process_s"
 #0 [d72d3ad0] crash_kexec at c028cfdb
 #1 [d72d3b24] oops_end at c05c5322
 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60
 #3 [d72d3bec] bad_area at c0227fb6
 #4 [d72d3c00] do_page_fault at c05c72ec
 #5 [d72d3c80] error_code (via page_fault) at c05c47a4
    EAX: 00000000  EBX: 000c0000  ECX: 00000001  EDX: 00000807  EBP: 000c0000
    DS:  007b      ESI: 00000001  ES:  007b      EDI: f3000a80  GS:  6f50
    CS:  0060      EIP: c030b15a  ERR: ffffffff  EFLAGS: 00010002
 torvalds#6 [d72d3cb4] isolate_migratepages at c030b15a
 torvalds#7 [d72d3d1] zone_watermark_ok at c02d26cb
 torvalds#8 [d72d3d2c] compact_zone at c030b8de
 torvalds#9 [d72d3d68] compact_zone_order at c030bba1
torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84
torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7
torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7
torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97
torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845
torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb
torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6
torvalds#17 [d72d3f30] do_page_fault at c05c70ed
torvalds#18 [d72d3fb0] error_code (via page_fault) at c05c47a4
    EAX: b71ff000  EBX: 00000001  ECX: 00001600  EDX: 00000431
    DS:  007b      ESI: 08048950  ES:  007b      EDI: bfaa3788
    SS:  007b      ESP: bfaa36e0  EBP: bfaa3828  GS:  6f50
    CS:  0073      EIP: 080487c8  ERR: ffffffff  EFLAGS: 00010202

It was also reported by Herbert van den Bergh against 3.1-based kernel
with the following snippet from the console log.

BUG: unable to handle kernel paging request at 01c00008
IP: [<c0522399>] isolate_migratepages+0x119/0x390
*pdpt = 000000002f7ce001 *pde = 0000000000000000

It is expected that it also affects 3.2.x and current mainline.

The problem is that pfn_valid is only called on the first PFN being
checked and that PFN is not necessarily aligned.  Lets say we have a case
like this

H = MAX_ORDER_NR_PAGES boundary
| = pageblock boundary
m = cc->migrate_pfn
f = cc->free_pfn
o = memory hole

H------|------H------|----m-Hoooooo|ooooooH-f----|------H

The migrate_pfn is just below a memory hole and the free scanner is beyond
the hole.  When isolate_migratepages started, it scans from migrate_pfn to
migrate_pfn+pageblock_nr_pages which is now in a memory hole.  It checks
pfn_valid() on the first PFN but then scans into the hole where there are
not necessarily valid struct pages.

This patch ensures that isolate_migratepages calls pfn_valid when
necessary.

Reported-by: Herbert van den Bergh <[email protected]>
Tested-by: Herbert van den Bergh <[email protected]>
Signed-off-by: Mel Gorman <[email protected]>
Acked-by: Michal Nazarewicz <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Tim Gardner <[email protected]>
koenkooi pushed a commit to koenkooi/linux that referenced this pull request Apr 19, 2012
…S block during isolation for migration

commit 0bf380b upstream.

When isolating for migration, migration starts at the start of a zone
which is not necessarily pageblock aligned.  Further, it stops isolating
when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally
not aligned.  This allows isolate_migratepages() to call pfn_to_page() on
an invalid PFN which can result in a crash.  This was originally reported
against a 3.0-based kernel with the following trace in a crash dump.

PID: 9902   TASK: d47aecd0  CPU: 0   COMMAND: "memcg_process_s"
 #0 [d72d3ad0] crash_kexec at c028cfdb
 #1 [d72d3b24] oops_end at c05c5322
 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60
 #3 [d72d3bec] bad_area at c0227fb6
 #4 [d72d3c00] do_page_fault at c05c72ec
 #5 [d72d3c80] error_code (via page_fault) at c05c47a4
    EAX: 00000000  EBX: 000c0000  ECX: 00000001  EDX: 00000807  EBP: 000c0000
    DS:  007b      ESI: 00000001  ES:  007b      EDI: f3000a80  GS:  6f50
    CS:  0060      EIP: c030b15a  ERR: ffffffff  EFLAGS: 00010002
 #6 [d72d3cb4] isolate_migratepages at c030b15a
 #7 [d72d3d1] zone_watermark_ok at c02d26cb
 #8 [d72d3d2c] compact_zone at c030b8de
 #9 [d72d3d68] compact_zone_order at c030bba1
torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84
torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7
torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7
torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97
torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845
torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb
torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6
torvalds#17 [d72d3f30] do_page_fault at c05c70ed
torvalds#18 [d72d3fb0] error_code (via page_fault) at c05c47a4
    EAX: b71ff000  EBX: 00000001  ECX: 00001600  EDX: 00000431
    DS:  007b      ESI: 08048950  ES:  007b      EDI: bfaa3788
    SS:  007b      ESP: bfaa36e0  EBP: bfaa3828  GS:  6f50
    CS:  0073      EIP: 080487c8  ERR: ffffffff  EFLAGS: 00010202

It was also reported by Herbert van den Bergh against 3.1-based kernel
with the following snippet from the console log.

BUG: unable to handle kernel paging request at 01c00008
IP: [<c0522399>] isolate_migratepages+0x119/0x390
*pdpt = 000000002f7ce001 *pde = 0000000000000000

It is expected that it also affects 3.2.x and current mainline.

The problem is that pfn_valid is only called on the first PFN being
checked and that PFN is not necessarily aligned.  Lets say we have a case
like this

H = MAX_ORDER_NR_PAGES boundary
| = pageblock boundary
m = cc->migrate_pfn
f = cc->free_pfn
o = memory hole

H------|------H------|----m-Hoooooo|ooooooH-f----|------H

The migrate_pfn is just below a memory hole and the free scanner is beyond
the hole.  When isolate_migratepages started, it scans from migrate_pfn to
migrate_pfn+pageblock_nr_pages which is now in a memory hole.  It checks
pfn_valid() on the first PFN but then scans into the hole where there are
not necessarily valid struct pages.

This patch ensures that isolate_migratepages calls pfn_valid when
necessary.

Reported-by: Herbert van den Bergh <[email protected]>
Tested-by: Herbert van den Bergh <[email protected]>
Signed-off-by: Mel Gorman <[email protected]>
Acked-by: Michal Nazarewicz <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
koenkooi pushed a commit to koenkooi/linux that referenced this pull request May 4, 2012
…S block during isolation for migration

commit 0bf380b upstream.

When isolating for migration, migration starts at the start of a zone
which is not necessarily pageblock aligned.  Further, it stops isolating
when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally
not aligned.  This allows isolate_migratepages() to call pfn_to_page() on
an invalid PFN which can result in a crash.  This was originally reported
against a 3.0-based kernel with the following trace in a crash dump.

PID: 9902   TASK: d47aecd0  CPU: 0   COMMAND: "memcg_process_s"
 #0 [d72d3ad0] crash_kexec at c028cfdb
 #1 [d72d3b24] oops_end at c05c5322
 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60
 #3 [d72d3bec] bad_area at c0227fb6
 #4 [d72d3c00] do_page_fault at c05c72ec
 #5 [d72d3c80] error_code (via page_fault) at c05c47a4
    EAX: 00000000  EBX: 000c0000  ECX: 00000001  EDX: 00000807  EBP: 000c0000
    DS:  007b      ESI: 00000001  ES:  007b      EDI: f3000a80  GS:  6f50
    CS:  0060      EIP: c030b15a  ERR: ffffffff  EFLAGS: 00010002
 #6 [d72d3cb4] isolate_migratepages at c030b15a
 #7 [d72d3d1] zone_watermark_ok at c02d26cb
 #8 [d72d3d2c] compact_zone at c030b8de
 #9 [d72d3d68] compact_zone_order at c030bba1
torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84
torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7
torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7
torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97
torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845
torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb
torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6
torvalds#17 [d72d3f30] do_page_fault at c05c70ed
torvalds#18 [d72d3fb0] error_code (via page_fault) at c05c47a4
    EAX: b71ff000  EBX: 00000001  ECX: 00001600  EDX: 00000431
    DS:  007b      ESI: 08048950  ES:  007b      EDI: bfaa3788
    SS:  007b      ESP: bfaa36e0  EBP: bfaa3828  GS:  6f50
    CS:  0073      EIP: 080487c8  ERR: ffffffff  EFLAGS: 00010202

It was also reported by Herbert van den Bergh against 3.1-based kernel
with the following snippet from the console log.

BUG: unable to handle kernel paging request at 01c00008
IP: [<c0522399>] isolate_migratepages+0x119/0x390
*pdpt = 000000002f7ce001 *pde = 0000000000000000

It is expected that it also affects 3.2.x and current mainline.

The problem is that pfn_valid is only called on the first PFN being
checked and that PFN is not necessarily aligned.  Lets say we have a case
like this

H = MAX_ORDER_NR_PAGES boundary
| = pageblock boundary
m = cc->migrate_pfn
f = cc->free_pfn
o = memory hole

H------|------H------|----m-Hoooooo|ooooooH-f----|------H

The migrate_pfn is just below a memory hole and the free scanner is beyond
the hole.  When isolate_migratepages started, it scans from migrate_pfn to
migrate_pfn+pageblock_nr_pages which is now in a memory hole.  It checks
pfn_valid() on the first PFN but then scans into the hole where there are
not necessarily valid struct pages.

This patch ensures that isolate_migratepages calls pfn_valid when
necessary.

Reported-by: Herbert van den Bergh <[email protected]>
Tested-by: Herbert van den Bergh <[email protected]>
Signed-off-by: Mel Gorman <[email protected]>
Acked-by: Michal Nazarewicz <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
koenkooi pushed a commit to koenkooi/linux that referenced this pull request May 4, 2012
…S block during isolation for migration

commit 0bf380b upstream.

When isolating for migration, migration starts at the start of a zone
which is not necessarily pageblock aligned.  Further, it stops isolating
when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally
not aligned.  This allows isolate_migratepages() to call pfn_to_page() on
an invalid PFN which can result in a crash.  This was originally reported
against a 3.0-based kernel with the following trace in a crash dump.

PID: 9902   TASK: d47aecd0  CPU: 0   COMMAND: "memcg_process_s"
 #0 [d72d3ad0] crash_kexec at c028cfdb
 #1 [d72d3b24] oops_end at c05c5322
 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60
 #3 [d72d3bec] bad_area at c0227fb6
 #4 [d72d3c00] do_page_fault at c05c72ec
 #5 [d72d3c80] error_code (via page_fault) at c05c47a4
    EAX: 00000000  EBX: 000c0000  ECX: 00000001  EDX: 00000807  EBP: 000c0000
    DS:  007b      ESI: 00000001  ES:  007b      EDI: f3000a80  GS:  6f50
    CS:  0060      EIP: c030b15a  ERR: ffffffff  EFLAGS: 00010002
 #6 [d72d3cb4] isolate_migratepages at c030b15a
 #7 [d72d3d1] zone_watermark_ok at c02d26cb
 #8 [d72d3d2c] compact_zone at c030b8de
 #9 [d72d3d68] compact_zone_order at c030bba1
torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84
torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7
torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7
torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97
torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845
torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb
torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6
torvalds#17 [d72d3f30] do_page_fault at c05c70ed
torvalds#18 [d72d3fb0] error_code (via page_fault) at c05c47a4
    EAX: b71ff000  EBX: 00000001  ECX: 00001600  EDX: 00000431
    DS:  007b      ESI: 08048950  ES:  007b      EDI: bfaa3788
    SS:  007b      ESP: bfaa36e0  EBP: bfaa3828  GS:  6f50
    CS:  0073      EIP: 080487c8  ERR: ffffffff  EFLAGS: 00010202

It was also reported by Herbert van den Bergh against 3.1-based kernel
with the following snippet from the console log.

BUG: unable to handle kernel paging request at 01c00008
IP: [<c0522399>] isolate_migratepages+0x119/0x390
*pdpt = 000000002f7ce001 *pde = 0000000000000000

It is expected that it also affects 3.2.x and current mainline.

The problem is that pfn_valid is only called on the first PFN being
checked and that PFN is not necessarily aligned.  Lets say we have a case
like this

H = MAX_ORDER_NR_PAGES boundary
| = pageblock boundary
m = cc->migrate_pfn
f = cc->free_pfn
o = memory hole

H------|------H------|----m-Hoooooo|ooooooH-f----|------H

The migrate_pfn is just below a memory hole and the free scanner is beyond
the hole.  When isolate_migratepages started, it scans from migrate_pfn to
migrate_pfn+pageblock_nr_pages which is now in a memory hole.  It checks
pfn_valid() on the first PFN but then scans into the hole where there are
not necessarily valid struct pages.

This patch ensures that isolate_migratepages calls pfn_valid when
necessary.

Reported-by: Herbert van den Bergh <[email protected]>
Tested-by: Herbert van den Bergh <[email protected]>
Signed-off-by: Mel Gorman <[email protected]>
Acked-by: Michal Nazarewicz <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
koenkooi pushed a commit to koenkooi/linux that referenced this pull request May 5, 2012
…S block during isolation for migration

commit 0bf380b upstream.

When isolating for migration, migration starts at the start of a zone
which is not necessarily pageblock aligned.  Further, it stops isolating
when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally
not aligned.  This allows isolate_migratepages() to call pfn_to_page() on
an invalid PFN which can result in a crash.  This was originally reported
against a 3.0-based kernel with the following trace in a crash dump.

PID: 9902   TASK: d47aecd0  CPU: 0   COMMAND: "memcg_process_s"
 #0 [d72d3ad0] crash_kexec at c028cfdb
 #1 [d72d3b24] oops_end at c05c5322
 #2 [d72d3b38] __bad_area_nosemaphore at c0227e60
 #3 [d72d3bec] bad_area at c0227fb6
 #4 [d72d3c00] do_page_fault at c05c72ec
 #5 [d72d3c80] error_code (via page_fault) at c05c47a4
    EAX: 00000000  EBX: 000c0000  ECX: 00000001  EDX: 00000807  EBP: 000c0000
    DS:  007b      ESI: 00000001  ES:  007b      EDI: f3000a80  GS:  6f50
    CS:  0060      EIP: c030b15a  ERR: ffffffff  EFLAGS: 00010002
 #6 [d72d3cb4] isolate_migratepages at c030b15a
 #7 [d72d3d1] zone_watermark_ok at c02d26cb
 #8 [d72d3d2c] compact_zone at c030b8de
 #9 [d72d3d68] compact_zone_order at c030bba1
torvalds#10 [d72d3db4] try_to_compact_pages at c030bc84
torvalds#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7
torvalds#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7
torvalds#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97
torvalds#14 [d72d3eb8] alloc_pages_vma at c030a845
torvalds#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb
torvalds#16 [d72d3f00] handle_mm_fault at c02f36c6
torvalds#17 [d72d3f30] do_page_fault at c05c70ed
torvalds#18 [d72d3fb0] error_code (via page_fault) at c05c47a4
    EAX: b71ff000  EBX: 00000001  ECX: 00001600  EDX: 00000431
    DS:  007b      ESI: 08048950  ES:  007b      EDI: bfaa3788
    SS:  007b      ESP: bfaa36e0  EBP: bfaa3828  GS:  6f50
    CS:  0073      EIP: 080487c8  ERR: ffffffff  EFLAGS: 00010202

It was also reported by Herbert van den Bergh against 3.1-based kernel
with the following snippet from the console log.

BUG: unable to handle kernel paging request at 01c00008
IP: [<c0522399>] isolate_migratepages+0x119/0x390
*pdpt = 000000002f7ce001 *pde = 0000000000000000

It is expected that it also affects 3.2.x and current mainline.

The problem is that pfn_valid is only called on the first PFN being
checked and that PFN is not necessarily aligned.  Lets say we have a case
like this

H = MAX_ORDER_NR_PAGES boundary
| = pageblock boundary
m = cc->migrate_pfn
f = cc->free_pfn
o = memory hole

H------|------H------|----m-Hoooooo|ooooooH-f----|------H

The migrate_pfn is just below a memory hole and the free scanner is beyond
the hole.  When isolate_migratepages started, it scans from migrate_pfn to
migrate_pfn+pageblock_nr_pages which is now in a memory hole.  It checks
pfn_valid() on the first PFN but then scans into the hole where there are
not necessarily valid struct pages.

This patch ensures that isolate_migratepages calls pfn_valid when
necessary.

Reported-by: Herbert van den Bergh <[email protected]>
Tested-by: Herbert van den Bergh <[email protected]>
Signed-off-by: Mel Gorman <[email protected]>
Acked-by: Michal Nazarewicz <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
mj22226 pushed a commit to mj22226/linux that referenced this pull request Oct 8, 2024
commit ac01c8c upstream.

AddressSanitizer found a use-after-free bug in the symbol code which
manifested as 'perf top' segfaulting.

  ==1238389==ERROR: AddressSanitizer: heap-use-after-free on address 0x60b00c48844b at pc 0x5650d8035961 bp 0x7f751aaecc90 sp 0x7f751aaecc80
  READ of size 1 at 0x60b00c48844b thread T193
      #0 0x5650d8035960 in _sort__sym_cmp util/sort.c:310
      #1 0x5650d8043744 in hist_entry__cmp util/hist.c:1286
      #2 0x5650d8043951 in hists__findnew_entry util/hist.c:614
      #3 0x5650d804568f in __hists__add_entry util/hist.c:754
      #4 0x5650d8045bf9 in hists__add_entry util/hist.c:772
      #5 0x5650d8045df1 in iter_add_single_normal_entry util/hist.c:997
      torvalds#6 0x5650d8043326 in hist_entry_iter__add util/hist.c:1242
      torvalds#7 0x5650d7ceeefe in perf_event__process_sample /home/matt/src/linux/tools/perf/builtin-top.c:845
      torvalds#8 0x5650d7ceeefe in deliver_event /home/matt/src/linux/tools/perf/builtin-top.c:1208
      torvalds#9 0x5650d7fdb51b in do_flush util/ordered-events.c:245
      torvalds#10 0x5650d7fdb51b in __ordered_events__flush util/ordered-events.c:324
      torvalds#11 0x5650d7ced743 in process_thread /home/matt/src/linux/tools/perf/builtin-top.c:1120
      torvalds#12 0x7f757ef1f133 in start_thread nptl/pthread_create.c:442
      torvalds#13 0x7f757ef9f7db in clone3 ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81

When updating hist maps it's also necessary to update the hist symbol
reference because the old one gets freed in map__put().

While this bug was probably introduced with 5c24b67 ("perf
tools: Replace map->referenced & maps->removed_maps with map->refcnt"),
the symbol objects were leaked until c087e94 ("perf machine:
Fix refcount usage when processing PERF_RECORD_KSYMBOL") was merged so
the bug was masked.

Fixes: c087e94 ("perf machine: Fix refcount usage when processing PERF_RECORD_KSYMBOL")
Reported-by: Yunzhao Li <[email protected]>
Signed-off-by: Matt Fleming (Cloudflare) <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: [email protected]
Cc: Namhyung Kim <[email protected]>
Cc: Riccardo Mancini <[email protected]>
Cc: [email protected] # v5.13+
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
mj22226 pushed a commit to mj22226/linux that referenced this pull request Oct 8, 2024
commit 9af2efe upstream.

The fields in the hist_entry are filled on-demand which means they only
have meaningful values when relevant sort keys are used.

So if neither of 'dso' nor 'sym' sort keys are used, the map/symbols in
the hist entry can be garbage.  So it shouldn't access it
unconditionally.

I got a segfault, when I wanted to see cgroup profiles.

  $ sudo perf record -a --all-cgroups --synth=cgroup true

  $ sudo perf report -s cgroup

  Program received signal SIGSEGV, Segmentation fault.
  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  48		return RC_CHK_ACCESS(map)->dso;
  (gdb) bt
  #0  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  #1  0x00005555557aa39b in map__load (map=0x0) at util/map.c:344
  #2  0x00005555557aa592 in map__find_symbol (map=0x0, addr=140736115941088) at util/map.c:385
  #3  0x00005555557ef000 in hists__findnew_entry (hists=0x555556039d60, entry=0x7fffffffa4c0, al=0x7fffffffa8c0, sample_self=true)
      at util/hist.c:644
  #4  0x00005555557ef61c in __hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      block_info=0x0, sample=0x7fffffffaa90, sample_self=true, ops=0x0) at util/hist.c:761
  #5  0x00005555557ef71f in hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      sample=0x7fffffffaa90, sample_self=true) at util/hist.c:779
  torvalds#6  0x00005555557f00fb in iter_add_single_normal_entry (iter=0x7fffffffa900, al=0x7fffffffa8c0) at util/hist.c:1015
  torvalds#7  0x00005555557f09a7 in hist_entry_iter__add (iter=0x7fffffffa900, al=0x7fffffffa8c0, max_stack_depth=127, arg=0x7fffffffbce0)
      at util/hist.c:1260
  torvalds#8  0x00005555555ba7ce in process_sample_event (tool=0x7fffffffbce0, event=0x7ffff7c14128, sample=0x7fffffffaa90, evsel=0x555556039ad0,
      machine=0x5555560388e8) at builtin-report.c:334
  torvalds#9  0x00005555557b30c8 in evlist__deliver_sample (evlist=0x555556039010, tool=0x7fffffffbce0, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, evsel=0x555556039ad0, machine=0x5555560388e8) at util/session.c:1232
  torvalds#10 0x00005555557b32bc in machines__deliver_event (machines=0x5555560388e8, evlist=0x555556039010, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, tool=0x7fffffffbce0, file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1271
  torvalds#11 0x00005555557b3848 in perf_session__deliver_event (session=0x5555560386d0, event=0x7ffff7c14128, tool=0x7fffffffbce0,
      file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1354
  torvalds#12 0x00005555557affaf in ordered_events__deliver_event (oe=0x555556038e60, event=0x555556135aa0) at util/session.c:132
  torvalds#13 0x00005555557bb605 in do_flush (oe=0x555556038e60, show_progress=false) at util/ordered-events.c:245
  torvalds#14 0x00005555557bb95c in __ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND, timestamp=0) at util/ordered-events.c:324
  torvalds#15 0x00005555557bba46 in ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND) at util/ordered-events.c:342
  torvalds#16 0x00005555557b1b3b in perf_event__process_finished_round (tool=0x7fffffffbce0, event=0x7ffff7c15bb8, oe=0x555556038e60)
      at util/session.c:780
  torvalds#17 0x00005555557b3b27 in perf_session__process_user_event (session=0x5555560386d0, event=0x7ffff7c15bb8, file_offset=117688,
      file_path=0x555556038ff0 "perf.data") at util/session.c:1406

As you can see the entry->ms.map was NULL even if he->ms.map has a
value.  This is because 'sym' sort key is not given, so it cannot assume
whether he->ms.sym and entry->ms.sym is the same.  I only checked the
'sym' sort key here as it implies 'dso' behavior (so maps are the same).

Fixes: ac01c8c ("perf hist: Update hist symbol when updating maps")
Signed-off-by: Namhyung Kim <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Matt Fleming <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
KexyBiscuit pushed a commit to AOSC-Tracking/linux that referenced this pull request Oct 8, 2024
commit ac01c8c upstream.

AddressSanitizer found a use-after-free bug in the symbol code which
manifested as 'perf top' segfaulting.

  ==1238389==ERROR: AddressSanitizer: heap-use-after-free on address 0x60b00c48844b at pc 0x5650d8035961 bp 0x7f751aaecc90 sp 0x7f751aaecc80
  READ of size 1 at 0x60b00c48844b thread T193
      #0 0x5650d8035960 in _sort__sym_cmp util/sort.c:310
      #1 0x5650d8043744 in hist_entry__cmp util/hist.c:1286
      #2 0x5650d8043951 in hists__findnew_entry util/hist.c:614
      #3 0x5650d804568f in __hists__add_entry util/hist.c:754
      #4 0x5650d8045bf9 in hists__add_entry util/hist.c:772
      #5 0x5650d8045df1 in iter_add_single_normal_entry util/hist.c:997
      torvalds#6 0x5650d8043326 in hist_entry_iter__add util/hist.c:1242
      torvalds#7 0x5650d7ceeefe in perf_event__process_sample /home/matt/src/linux/tools/perf/builtin-top.c:845
      torvalds#8 0x5650d7ceeefe in deliver_event /home/matt/src/linux/tools/perf/builtin-top.c:1208
      torvalds#9 0x5650d7fdb51b in do_flush util/ordered-events.c:245
      torvalds#10 0x5650d7fdb51b in __ordered_events__flush util/ordered-events.c:324
      torvalds#11 0x5650d7ced743 in process_thread /home/matt/src/linux/tools/perf/builtin-top.c:1120
      torvalds#12 0x7f757ef1f133 in start_thread nptl/pthread_create.c:442
      torvalds#13 0x7f757ef9f7db in clone3 ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81

When updating hist maps it's also necessary to update the hist symbol
reference because the old one gets freed in map__put().

While this bug was probably introduced with 5c24b67 ("perf
tools: Replace map->referenced & maps->removed_maps with map->refcnt"),
the symbol objects were leaked until c087e94 ("perf machine:
Fix refcount usage when processing PERF_RECORD_KSYMBOL") was merged so
the bug was masked.

Fixes: c087e94 ("perf machine: Fix refcount usage when processing PERF_RECORD_KSYMBOL")
Reported-by: Yunzhao Li <[email protected]>
Signed-off-by: Matt Fleming (Cloudflare) <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: [email protected]
Cc: Namhyung Kim <[email protected]>
Cc: Riccardo Mancini <[email protected]>
Cc: [email protected] # v5.13+
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
KexyBiscuit pushed a commit to AOSC-Tracking/linux that referenced this pull request Oct 8, 2024
commit 9af2efe upstream.

The fields in the hist_entry are filled on-demand which means they only
have meaningful values when relevant sort keys are used.

So if neither of 'dso' nor 'sym' sort keys are used, the map/symbols in
the hist entry can be garbage.  So it shouldn't access it
unconditionally.

I got a segfault, when I wanted to see cgroup profiles.

  $ sudo perf record -a --all-cgroups --synth=cgroup true

  $ sudo perf report -s cgroup

  Program received signal SIGSEGV, Segmentation fault.
  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  48		return RC_CHK_ACCESS(map)->dso;
  (gdb) bt
  #0  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  #1  0x00005555557aa39b in map__load (map=0x0) at util/map.c:344
  #2  0x00005555557aa592 in map__find_symbol (map=0x0, addr=140736115941088) at util/map.c:385
  #3  0x00005555557ef000 in hists__findnew_entry (hists=0x555556039d60, entry=0x7fffffffa4c0, al=0x7fffffffa8c0, sample_self=true)
      at util/hist.c:644
  #4  0x00005555557ef61c in __hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      block_info=0x0, sample=0x7fffffffaa90, sample_self=true, ops=0x0) at util/hist.c:761
  #5  0x00005555557ef71f in hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      sample=0x7fffffffaa90, sample_self=true) at util/hist.c:779
  torvalds#6  0x00005555557f00fb in iter_add_single_normal_entry (iter=0x7fffffffa900, al=0x7fffffffa8c0) at util/hist.c:1015
  torvalds#7  0x00005555557f09a7 in hist_entry_iter__add (iter=0x7fffffffa900, al=0x7fffffffa8c0, max_stack_depth=127, arg=0x7fffffffbce0)
      at util/hist.c:1260
  torvalds#8  0x00005555555ba7ce in process_sample_event (tool=0x7fffffffbce0, event=0x7ffff7c14128, sample=0x7fffffffaa90, evsel=0x555556039ad0,
      machine=0x5555560388e8) at builtin-report.c:334
  torvalds#9  0x00005555557b30c8 in evlist__deliver_sample (evlist=0x555556039010, tool=0x7fffffffbce0, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, evsel=0x555556039ad0, machine=0x5555560388e8) at util/session.c:1232
  torvalds#10 0x00005555557b32bc in machines__deliver_event (machines=0x5555560388e8, evlist=0x555556039010, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, tool=0x7fffffffbce0, file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1271
  torvalds#11 0x00005555557b3848 in perf_session__deliver_event (session=0x5555560386d0, event=0x7ffff7c14128, tool=0x7fffffffbce0,
      file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1354
  torvalds#12 0x00005555557affaf in ordered_events__deliver_event (oe=0x555556038e60, event=0x555556135aa0) at util/session.c:132
  torvalds#13 0x00005555557bb605 in do_flush (oe=0x555556038e60, show_progress=false) at util/ordered-events.c:245
  torvalds#14 0x00005555557bb95c in __ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND, timestamp=0) at util/ordered-events.c:324
  torvalds#15 0x00005555557bba46 in ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND) at util/ordered-events.c:342
  torvalds#16 0x00005555557b1b3b in perf_event__process_finished_round (tool=0x7fffffffbce0, event=0x7ffff7c15bb8, oe=0x555556038e60)
      at util/session.c:780
  torvalds#17 0x00005555557b3b27 in perf_session__process_user_event (session=0x5555560386d0, event=0x7ffff7c15bb8, file_offset=117688,
      file_path=0x555556038ff0 "perf.data") at util/session.c:1406

As you can see the entry->ms.map was NULL even if he->ms.map has a
value.  This is because 'sym' sort key is not given, so it cannot assume
whether he->ms.sym and entry->ms.sym is the same.  I only checked the
'sym' sort key here as it implies 'dso' behavior (so maps are the same).

Fixes: ac01c8c ("perf hist: Update hist symbol when updating maps")
Signed-off-by: Namhyung Kim <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Matt Fleming <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
intersectRaven pushed a commit to intersectRaven/linux that referenced this pull request Oct 10, 2024
commit ac01c8c upstream.

AddressSanitizer found a use-after-free bug in the symbol code which
manifested as 'perf top' segfaulting.

  ==1238389==ERROR: AddressSanitizer: heap-use-after-free on address 0x60b00c48844b at pc 0x5650d8035961 bp 0x7f751aaecc90 sp 0x7f751aaecc80
  READ of size 1 at 0x60b00c48844b thread T193
      #0 0x5650d8035960 in _sort__sym_cmp util/sort.c:310
      #1 0x5650d8043744 in hist_entry__cmp util/hist.c:1286
      #2 0x5650d8043951 in hists__findnew_entry util/hist.c:614
      #3 0x5650d804568f in __hists__add_entry util/hist.c:754
      #4 0x5650d8045bf9 in hists__add_entry util/hist.c:772
      #5 0x5650d8045df1 in iter_add_single_normal_entry util/hist.c:997
      torvalds#6 0x5650d8043326 in hist_entry_iter__add util/hist.c:1242
      torvalds#7 0x5650d7ceeefe in perf_event__process_sample /home/matt/src/linux/tools/perf/builtin-top.c:845
      torvalds#8 0x5650d7ceeefe in deliver_event /home/matt/src/linux/tools/perf/builtin-top.c:1208
      torvalds#9 0x5650d7fdb51b in do_flush util/ordered-events.c:245
      torvalds#10 0x5650d7fdb51b in __ordered_events__flush util/ordered-events.c:324
      torvalds#11 0x5650d7ced743 in process_thread /home/matt/src/linux/tools/perf/builtin-top.c:1120
      torvalds#12 0x7f757ef1f133 in start_thread nptl/pthread_create.c:442
      torvalds#13 0x7f757ef9f7db in clone3 ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81

When updating hist maps it's also necessary to update the hist symbol
reference because the old one gets freed in map__put().

While this bug was probably introduced with 5c24b67 ("perf
tools: Replace map->referenced & maps->removed_maps with map->refcnt"),
the symbol objects were leaked until c087e94 ("perf machine:
Fix refcount usage when processing PERF_RECORD_KSYMBOL") was merged so
the bug was masked.

Fixes: c087e94 ("perf machine: Fix refcount usage when processing PERF_RECORD_KSYMBOL")
Reported-by: Yunzhao Li <[email protected]>
Signed-off-by: Matt Fleming (Cloudflare) <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: [email protected]
Cc: Namhyung Kim <[email protected]>
Cc: Riccardo Mancini <[email protected]>
Cc: [email protected] # v5.13+
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
intersectRaven pushed a commit to intersectRaven/linux that referenced this pull request Oct 10, 2024
commit 9af2efe upstream.

The fields in the hist_entry are filled on-demand which means they only
have meaningful values when relevant sort keys are used.

So if neither of 'dso' nor 'sym' sort keys are used, the map/symbols in
the hist entry can be garbage.  So it shouldn't access it
unconditionally.

I got a segfault, when I wanted to see cgroup profiles.

  $ sudo perf record -a --all-cgroups --synth=cgroup true

  $ sudo perf report -s cgroup

  Program received signal SIGSEGV, Segmentation fault.
  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  48		return RC_CHK_ACCESS(map)->dso;
  (gdb) bt
  #0  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  #1  0x00005555557aa39b in map__load (map=0x0) at util/map.c:344
  #2  0x00005555557aa592 in map__find_symbol (map=0x0, addr=140736115941088) at util/map.c:385
  #3  0x00005555557ef000 in hists__findnew_entry (hists=0x555556039d60, entry=0x7fffffffa4c0, al=0x7fffffffa8c0, sample_self=true)
      at util/hist.c:644
  #4  0x00005555557ef61c in __hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      block_info=0x0, sample=0x7fffffffaa90, sample_self=true, ops=0x0) at util/hist.c:761
  #5  0x00005555557ef71f in hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      sample=0x7fffffffaa90, sample_self=true) at util/hist.c:779
  torvalds#6  0x00005555557f00fb in iter_add_single_normal_entry (iter=0x7fffffffa900, al=0x7fffffffa8c0) at util/hist.c:1015
  torvalds#7  0x00005555557f09a7 in hist_entry_iter__add (iter=0x7fffffffa900, al=0x7fffffffa8c0, max_stack_depth=127, arg=0x7fffffffbce0)
      at util/hist.c:1260
  torvalds#8  0x00005555555ba7ce in process_sample_event (tool=0x7fffffffbce0, event=0x7ffff7c14128, sample=0x7fffffffaa90, evsel=0x555556039ad0,
      machine=0x5555560388e8) at builtin-report.c:334
  torvalds#9  0x00005555557b30c8 in evlist__deliver_sample (evlist=0x555556039010, tool=0x7fffffffbce0, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, evsel=0x555556039ad0, machine=0x5555560388e8) at util/session.c:1232
  torvalds#10 0x00005555557b32bc in machines__deliver_event (machines=0x5555560388e8, evlist=0x555556039010, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, tool=0x7fffffffbce0, file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1271
  torvalds#11 0x00005555557b3848 in perf_session__deliver_event (session=0x5555560386d0, event=0x7ffff7c14128, tool=0x7fffffffbce0,
      file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1354
  torvalds#12 0x00005555557affaf in ordered_events__deliver_event (oe=0x555556038e60, event=0x555556135aa0) at util/session.c:132
  torvalds#13 0x00005555557bb605 in do_flush (oe=0x555556038e60, show_progress=false) at util/ordered-events.c:245
  torvalds#14 0x00005555557bb95c in __ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND, timestamp=0) at util/ordered-events.c:324
  torvalds#15 0x00005555557bba46 in ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND) at util/ordered-events.c:342
  torvalds#16 0x00005555557b1b3b in perf_event__process_finished_round (tool=0x7fffffffbce0, event=0x7ffff7c15bb8, oe=0x555556038e60)
      at util/session.c:780
  torvalds#17 0x00005555557b3b27 in perf_session__process_user_event (session=0x5555560386d0, event=0x7ffff7c15bb8, file_offset=117688,
      file_path=0x555556038ff0 "perf.data") at util/session.c:1406

As you can see the entry->ms.map was NULL even if he->ms.map has a
value.  This is because 'sym' sort key is not given, so it cannot assume
whether he->ms.sym and entry->ms.sym is the same.  I only checked the
'sym' sort key here as it implies 'dso' behavior (so maps are the same).

Fixes: ac01c8c ("perf hist: Update hist symbol when updating maps")
Signed-off-by: Namhyung Kim <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Matt Fleming <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
riccardv pushed a commit to riccardv/linux that referenced this pull request Oct 10, 2024
commit ac01c8c upstream.

AddressSanitizer found a use-after-free bug in the symbol code which
manifested as 'perf top' segfaulting.

  ==1238389==ERROR: AddressSanitizer: heap-use-after-free on address 0x60b00c48844b at pc 0x5650d8035961 bp 0x7f751aaecc90 sp 0x7f751aaecc80
  READ of size 1 at 0x60b00c48844b thread T193
      #0 0x5650d8035960 in _sort__sym_cmp util/sort.c:310
      #1 0x5650d8043744 in hist_entry__cmp util/hist.c:1286
      #2 0x5650d8043951 in hists__findnew_entry util/hist.c:614
      #3 0x5650d804568f in __hists__add_entry util/hist.c:754
      #4 0x5650d8045bf9 in hists__add_entry util/hist.c:772
      #5 0x5650d8045df1 in iter_add_single_normal_entry util/hist.c:997
      torvalds#6 0x5650d8043326 in hist_entry_iter__add util/hist.c:1242
      torvalds#7 0x5650d7ceeefe in perf_event__process_sample /home/matt/src/linux/tools/perf/builtin-top.c:845
      torvalds#8 0x5650d7ceeefe in deliver_event /home/matt/src/linux/tools/perf/builtin-top.c:1208
      torvalds#9 0x5650d7fdb51b in do_flush util/ordered-events.c:245
      torvalds#10 0x5650d7fdb51b in __ordered_events__flush util/ordered-events.c:324
      torvalds#11 0x5650d7ced743 in process_thread /home/matt/src/linux/tools/perf/builtin-top.c:1120
      torvalds#12 0x7f757ef1f133 in start_thread nptl/pthread_create.c:442
      torvalds#13 0x7f757ef9f7db in clone3 ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81

When updating hist maps it's also necessary to update the hist symbol
reference because the old one gets freed in map__put().

While this bug was probably introduced with 5c24b67 ("perf
tools: Replace map->referenced & maps->removed_maps with map->refcnt"),
the symbol objects were leaked until c087e94 ("perf machine:
Fix refcount usage when processing PERF_RECORD_KSYMBOL") was merged so
the bug was masked.

Fixes: c087e94 ("perf machine: Fix refcount usage when processing PERF_RECORD_KSYMBOL")
Reported-by: Yunzhao Li <[email protected]>
Signed-off-by: Matt Fleming (Cloudflare) <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: [email protected]
Cc: Namhyung Kim <[email protected]>
Cc: Riccardo Mancini <[email protected]>
Cc: [email protected] # v5.13+
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
riccardv pushed a commit to riccardv/linux that referenced this pull request Oct 10, 2024
commit 9af2efe upstream.

The fields in the hist_entry are filled on-demand which means they only
have meaningful values when relevant sort keys are used.

So if neither of 'dso' nor 'sym' sort keys are used, the map/symbols in
the hist entry can be garbage.  So it shouldn't access it
unconditionally.

I got a segfault, when I wanted to see cgroup profiles.

  $ sudo perf record -a --all-cgroups --synth=cgroup true

  $ sudo perf report -s cgroup

  Program received signal SIGSEGV, Segmentation fault.
  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  48		return RC_CHK_ACCESS(map)->dso;
  (gdb) bt
  #0  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  #1  0x00005555557aa39b in map__load (map=0x0) at util/map.c:344
  #2  0x00005555557aa592 in map__find_symbol (map=0x0, addr=140736115941088) at util/map.c:385
  #3  0x00005555557ef000 in hists__findnew_entry (hists=0x555556039d60, entry=0x7fffffffa4c0, al=0x7fffffffa8c0, sample_self=true)
      at util/hist.c:644
  #4  0x00005555557ef61c in __hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      block_info=0x0, sample=0x7fffffffaa90, sample_self=true, ops=0x0) at util/hist.c:761
  #5  0x00005555557ef71f in hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      sample=0x7fffffffaa90, sample_self=true) at util/hist.c:779
  torvalds#6  0x00005555557f00fb in iter_add_single_normal_entry (iter=0x7fffffffa900, al=0x7fffffffa8c0) at util/hist.c:1015
  torvalds#7  0x00005555557f09a7 in hist_entry_iter__add (iter=0x7fffffffa900, al=0x7fffffffa8c0, max_stack_depth=127, arg=0x7fffffffbce0)
      at util/hist.c:1260
  torvalds#8  0x00005555555ba7ce in process_sample_event (tool=0x7fffffffbce0, event=0x7ffff7c14128, sample=0x7fffffffaa90, evsel=0x555556039ad0,
      machine=0x5555560388e8) at builtin-report.c:334
  torvalds#9  0x00005555557b30c8 in evlist__deliver_sample (evlist=0x555556039010, tool=0x7fffffffbce0, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, evsel=0x555556039ad0, machine=0x5555560388e8) at util/session.c:1232
  torvalds#10 0x00005555557b32bc in machines__deliver_event (machines=0x5555560388e8, evlist=0x555556039010, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, tool=0x7fffffffbce0, file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1271
  torvalds#11 0x00005555557b3848 in perf_session__deliver_event (session=0x5555560386d0, event=0x7ffff7c14128, tool=0x7fffffffbce0,
      file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1354
  torvalds#12 0x00005555557affaf in ordered_events__deliver_event (oe=0x555556038e60, event=0x555556135aa0) at util/session.c:132
  torvalds#13 0x00005555557bb605 in do_flush (oe=0x555556038e60, show_progress=false) at util/ordered-events.c:245
  torvalds#14 0x00005555557bb95c in __ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND, timestamp=0) at util/ordered-events.c:324
  torvalds#15 0x00005555557bba46 in ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND) at util/ordered-events.c:342
  torvalds#16 0x00005555557b1b3b in perf_event__process_finished_round (tool=0x7fffffffbce0, event=0x7ffff7c15bb8, oe=0x555556038e60)
      at util/session.c:780
  torvalds#17 0x00005555557b3b27 in perf_session__process_user_event (session=0x5555560386d0, event=0x7ffff7c15bb8, file_offset=117688,
      file_path=0x555556038ff0 "perf.data") at util/session.c:1406

As you can see the entry->ms.map was NULL even if he->ms.map has a
value.  This is because 'sym' sort key is not given, so it cannot assume
whether he->ms.sym and entry->ms.sym is the same.  I only checked the
'sym' sort key here as it implies 'dso' behavior (so maps are the same).

Fixes: ac01c8c ("perf hist: Update hist symbol when updating maps")
Signed-off-by: Namhyung Kim <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Matt Fleming <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
1054009064 pushed a commit to 1054009064/linux that referenced this pull request Oct 10, 2024
commit ac01c8c upstream.

AddressSanitizer found a use-after-free bug in the symbol code which
manifested as 'perf top' segfaulting.

  ==1238389==ERROR: AddressSanitizer: heap-use-after-free on address 0x60b00c48844b at pc 0x5650d8035961 bp 0x7f751aaecc90 sp 0x7f751aaecc80
  READ of size 1 at 0x60b00c48844b thread T193
      #0 0x5650d8035960 in _sort__sym_cmp util/sort.c:310
      #1 0x5650d8043744 in hist_entry__cmp util/hist.c:1286
      #2 0x5650d8043951 in hists__findnew_entry util/hist.c:614
      #3 0x5650d804568f in __hists__add_entry util/hist.c:754
      #4 0x5650d8045bf9 in hists__add_entry util/hist.c:772
      #5 0x5650d8045df1 in iter_add_single_normal_entry util/hist.c:997
      torvalds#6 0x5650d8043326 in hist_entry_iter__add util/hist.c:1242
      torvalds#7 0x5650d7ceeefe in perf_event__process_sample /home/matt/src/linux/tools/perf/builtin-top.c:845
      torvalds#8 0x5650d7ceeefe in deliver_event /home/matt/src/linux/tools/perf/builtin-top.c:1208
      torvalds#9 0x5650d7fdb51b in do_flush util/ordered-events.c:245
      torvalds#10 0x5650d7fdb51b in __ordered_events__flush util/ordered-events.c:324
      torvalds#11 0x5650d7ced743 in process_thread /home/matt/src/linux/tools/perf/builtin-top.c:1120
      torvalds#12 0x7f757ef1f133 in start_thread nptl/pthread_create.c:442
      torvalds#13 0x7f757ef9f7db in clone3 ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81

When updating hist maps it's also necessary to update the hist symbol
reference because the old one gets freed in map__put().

While this bug was probably introduced with 5c24b67 ("perf
tools: Replace map->referenced & maps->removed_maps with map->refcnt"),
the symbol objects were leaked until c087e94 ("perf machine:
Fix refcount usage when processing PERF_RECORD_KSYMBOL") was merged so
the bug was masked.

Fixes: c087e94 ("perf machine: Fix refcount usage when processing PERF_RECORD_KSYMBOL")
Reported-by: Yunzhao Li <[email protected]>
Signed-off-by: Matt Fleming (Cloudflare) <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: [email protected]
Cc: Namhyung Kim <[email protected]>
Cc: Riccardo Mancini <[email protected]>
Cc: [email protected] # v5.13+
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
1054009064 pushed a commit to 1054009064/linux that referenced this pull request Oct 10, 2024
commit 9af2efe upstream.

The fields in the hist_entry are filled on-demand which means they only
have meaningful values when relevant sort keys are used.

So if neither of 'dso' nor 'sym' sort keys are used, the map/symbols in
the hist entry can be garbage.  So it shouldn't access it
unconditionally.

I got a segfault, when I wanted to see cgroup profiles.

  $ sudo perf record -a --all-cgroups --synth=cgroup true

  $ sudo perf report -s cgroup

  Program received signal SIGSEGV, Segmentation fault.
  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  48		return RC_CHK_ACCESS(map)->dso;
  (gdb) bt
  #0  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  #1  0x00005555557aa39b in map__load (map=0x0) at util/map.c:344
  #2  0x00005555557aa592 in map__find_symbol (map=0x0, addr=140736115941088) at util/map.c:385
  #3  0x00005555557ef000 in hists__findnew_entry (hists=0x555556039d60, entry=0x7fffffffa4c0, al=0x7fffffffa8c0, sample_self=true)
      at util/hist.c:644
  #4  0x00005555557ef61c in __hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      block_info=0x0, sample=0x7fffffffaa90, sample_self=true, ops=0x0) at util/hist.c:761
  #5  0x00005555557ef71f in hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      sample=0x7fffffffaa90, sample_self=true) at util/hist.c:779
  torvalds#6  0x00005555557f00fb in iter_add_single_normal_entry (iter=0x7fffffffa900, al=0x7fffffffa8c0) at util/hist.c:1015
  torvalds#7  0x00005555557f09a7 in hist_entry_iter__add (iter=0x7fffffffa900, al=0x7fffffffa8c0, max_stack_depth=127, arg=0x7fffffffbce0)
      at util/hist.c:1260
  torvalds#8  0x00005555555ba7ce in process_sample_event (tool=0x7fffffffbce0, event=0x7ffff7c14128, sample=0x7fffffffaa90, evsel=0x555556039ad0,
      machine=0x5555560388e8) at builtin-report.c:334
  torvalds#9  0x00005555557b30c8 in evlist__deliver_sample (evlist=0x555556039010, tool=0x7fffffffbce0, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, evsel=0x555556039ad0, machine=0x5555560388e8) at util/session.c:1232
  torvalds#10 0x00005555557b32bc in machines__deliver_event (machines=0x5555560388e8, evlist=0x555556039010, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, tool=0x7fffffffbce0, file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1271
  torvalds#11 0x00005555557b3848 in perf_session__deliver_event (session=0x5555560386d0, event=0x7ffff7c14128, tool=0x7fffffffbce0,
      file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1354
  torvalds#12 0x00005555557affaf in ordered_events__deliver_event (oe=0x555556038e60, event=0x555556135aa0) at util/session.c:132
  torvalds#13 0x00005555557bb605 in do_flush (oe=0x555556038e60, show_progress=false) at util/ordered-events.c:245
  torvalds#14 0x00005555557bb95c in __ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND, timestamp=0) at util/ordered-events.c:324
  torvalds#15 0x00005555557bba46 in ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND) at util/ordered-events.c:342
  torvalds#16 0x00005555557b1b3b in perf_event__process_finished_round (tool=0x7fffffffbce0, event=0x7ffff7c15bb8, oe=0x555556038e60)
      at util/session.c:780
  torvalds#17 0x00005555557b3b27 in perf_session__process_user_event (session=0x5555560386d0, event=0x7ffff7c15bb8, file_offset=117688,
      file_path=0x555556038ff0 "perf.data") at util/session.c:1406

As you can see the entry->ms.map was NULL even if he->ms.map has a
value.  This is because 'sym' sort key is not given, so it cannot assume
whether he->ms.sym and entry->ms.sym is the same.  I only checked the
'sym' sort key here as it implies 'dso' behavior (so maps are the same).

Fixes: ac01c8c ("perf hist: Update hist symbol when updating maps")
Signed-off-by: Namhyung Kim <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Matt Fleming <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
intel-lab-lkp pushed a commit to intel-lab-lkp/linux that referenced this pull request Oct 10, 2024
Dennis reports a boot crash on recent Lenovo laptops with a USB4 dock.

Since commit 0fc7088 ("thunderbolt: Reset USB4 v2 host router") and
commit 59a54c5 ("thunderbolt: Reset topology created by the boot
firmware"), USB4 v2 and v1 Host Routers are reset on probe of the
thunderbolt driver.

The reset clears the Presence Detect State and Data Link Layer Link Active
bits at the USB4 Host Router's Root Port and thus causes hot removal of
the dock.

The crash occurs when pciehp is unbound from one of the dock's Downstream
Ports:  pciehp creates a pci_slot on bind and destroys it on unbind.  The
pci_slot contains a pointer to the pci_bus below the Downstream Port, but
a reference on that pci_bus is never acquired.  The pci_bus is destroyed
before the pci_slot, so a use-after-free ensues when pci_slot_release()
accesses slot->bus.

In principle this should not happen because pci_stop_bus_device() unbinds
pciehp (and therefore destroys the pci_slot) before the pci_bus is
destroyed by pci_remove_bus_device().

However the stacktrace provided by Dennis shows that pciehp is unbound
from pci_remove_bus_device() instead of pci_stop_bus_device().
To understand the significance of this, one needs to know that the PCI
core uses a two step process to remove a portion of the hierarchy:  It
first unbinds all drivers in the sub-hierarchy in pci_stop_bus_device()
and then actually removes the devices in pci_remove_bus_device().
There is no precaution to prevent driver binding in-between
pci_stop_bus_device() and pci_remove_bus_device().

In Dennis' case, it seems removal of the hierarchy by pciehp races with
driver binding by pci_bus_add_devices().  pciehp is bound to the
Downstream Port after pci_stop_bus_device() has run, so it is unbound by
pci_remove_bus_device() instead of pci_stop_bus_device().  Because the
pci_bus has already been destroyed at that point, accesses to it result in
a use-after-free.

One might conclude that driver binding needs to be prevented after
pci_stop_bus_device() has run.  However it seems risky that pci_slot
points to pci_bus without holding a reference.  Solely relying on correct
ordering of driver unbind versus pci_bus destruction is certainly not
defensive programming.

If pci_slot has a need to access data in pci_bus, it ought to acquire a
reference.  Amend pci_create_slot() accordingly.  Dennis reports that the
crash is not reproducible with this change.

Abridged stacktrace:

  pcieport 0000:00:07.0: PME: Signaling with IRQ 156
  pcieport 0000:00:07.0: pciehp: Slot torvalds#12 AttnBtn- PwrCtrl- MRL- AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis- LLActRep+
  pci_bus 0000:20: dev 00, created physical slot 12
  pcieport 0000:00:07.0: pciehp: Slot(12): Card not present
  ...
  pcieport 0000:21:02.0: pciehp: pcie_disable_notification: SLOTCTRL d8 write cmd 0
  Oops: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b6b: 0000 [#1] PREEMPT SMP NOPTI
  CPU: 13 UID: 0 PID: 134 Comm: irq/156-pciehp Not tainted 6.11.0-devel+ #1
  RIP: 0010:dev_driver_string+0x12/0x40
  pci_destroy_slot
  pciehp_remove
  pcie_port_remove_service
  device_release_driver_internal
  bus_remove_device
  device_del
  device_unregister
  remove_iter
  device_for_each_child
  pcie_portdrv_remove
  pci_device_remove
  device_release_driver_internal
  bus_remove_device
  device_del
  pci_remove_bus_device (recursive invocation)
  pci_remove_bus_device
  pciehp_unconfigure_device
  pciehp_disable_slot
  pciehp_handle_presence_or_link_change
  pciehp_ist

Reported-by: Dennis Wassenberg <[email protected]>
Tested-by: Dennis Wassenberg <[email protected]>
Closes: https://lore.kernel.org/r/[email protected]/
Signed-off-by: Lukas Wunner <[email protected]>
Cc: [email protected]
mj22226 pushed a commit to mj22226/linux that referenced this pull request Oct 14, 2024
commit ac01c8c upstream.

AddressSanitizer found a use-after-free bug in the symbol code which
manifested as 'perf top' segfaulting.

  ==1238389==ERROR: AddressSanitizer: heap-use-after-free on address 0x60b00c48844b at pc 0x5650d8035961 bp 0x7f751aaecc90 sp 0x7f751aaecc80
  READ of size 1 at 0x60b00c48844b thread T193
      #0 0x5650d8035960 in _sort__sym_cmp util/sort.c:310
      #1 0x5650d8043744 in hist_entry__cmp util/hist.c:1286
      #2 0x5650d8043951 in hists__findnew_entry util/hist.c:614
      #3 0x5650d804568f in __hists__add_entry util/hist.c:754
      #4 0x5650d8045bf9 in hists__add_entry util/hist.c:772
      #5 0x5650d8045df1 in iter_add_single_normal_entry util/hist.c:997
      torvalds#6 0x5650d8043326 in hist_entry_iter__add util/hist.c:1242
      torvalds#7 0x5650d7ceeefe in perf_event__process_sample /home/matt/src/linux/tools/perf/builtin-top.c:845
      torvalds#8 0x5650d7ceeefe in deliver_event /home/matt/src/linux/tools/perf/builtin-top.c:1208
      torvalds#9 0x5650d7fdb51b in do_flush util/ordered-events.c:245
      torvalds#10 0x5650d7fdb51b in __ordered_events__flush util/ordered-events.c:324
      torvalds#11 0x5650d7ced743 in process_thread /home/matt/src/linux/tools/perf/builtin-top.c:1120
      torvalds#12 0x7f757ef1f133 in start_thread nptl/pthread_create.c:442
      torvalds#13 0x7f757ef9f7db in clone3 ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81

When updating hist maps it's also necessary to update the hist symbol
reference because the old one gets freed in map__put().

While this bug was probably introduced with 5c24b67 ("perf
tools: Replace map->referenced & maps->removed_maps with map->refcnt"),
the symbol objects were leaked until c087e94 ("perf machine:
Fix refcount usage when processing PERF_RECORD_KSYMBOL") was merged so
the bug was masked.

Fixes: c087e94 ("perf machine: Fix refcount usage when processing PERF_RECORD_KSYMBOL")
Reported-by: Yunzhao Li <[email protected]>
Signed-off-by: Matt Fleming (Cloudflare) <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: [email protected]
Cc: Namhyung Kim <[email protected]>
Cc: Riccardo Mancini <[email protected]>
Cc: [email protected] # v5.13+
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
mj22226 pushed a commit to mj22226/linux that referenced this pull request Oct 14, 2024
commit 9af2efe upstream.

The fields in the hist_entry are filled on-demand which means they only
have meaningful values when relevant sort keys are used.

So if neither of 'dso' nor 'sym' sort keys are used, the map/symbols in
the hist entry can be garbage.  So it shouldn't access it
unconditionally.

I got a segfault, when I wanted to see cgroup profiles.

  $ sudo perf record -a --all-cgroups --synth=cgroup true

  $ sudo perf report -s cgroup

  Program received signal SIGSEGV, Segmentation fault.
  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  48		return RC_CHK_ACCESS(map)->dso;
  (gdb) bt
  #0  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  #1  0x00005555557aa39b in map__load (map=0x0) at util/map.c:344
  #2  0x00005555557aa592 in map__find_symbol (map=0x0, addr=140736115941088) at util/map.c:385
  #3  0x00005555557ef000 in hists__findnew_entry (hists=0x555556039d60, entry=0x7fffffffa4c0, al=0x7fffffffa8c0, sample_self=true)
      at util/hist.c:644
  #4  0x00005555557ef61c in __hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      block_info=0x0, sample=0x7fffffffaa90, sample_self=true, ops=0x0) at util/hist.c:761
  #5  0x00005555557ef71f in hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      sample=0x7fffffffaa90, sample_self=true) at util/hist.c:779
  torvalds#6  0x00005555557f00fb in iter_add_single_normal_entry (iter=0x7fffffffa900, al=0x7fffffffa8c0) at util/hist.c:1015
  torvalds#7  0x00005555557f09a7 in hist_entry_iter__add (iter=0x7fffffffa900, al=0x7fffffffa8c0, max_stack_depth=127, arg=0x7fffffffbce0)
      at util/hist.c:1260
  torvalds#8  0x00005555555ba7ce in process_sample_event (tool=0x7fffffffbce0, event=0x7ffff7c14128, sample=0x7fffffffaa90, evsel=0x555556039ad0,
      machine=0x5555560388e8) at builtin-report.c:334
  torvalds#9  0x00005555557b30c8 in evlist__deliver_sample (evlist=0x555556039010, tool=0x7fffffffbce0, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, evsel=0x555556039ad0, machine=0x5555560388e8) at util/session.c:1232
  torvalds#10 0x00005555557b32bc in machines__deliver_event (machines=0x5555560388e8, evlist=0x555556039010, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, tool=0x7fffffffbce0, file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1271
  torvalds#11 0x00005555557b3848 in perf_session__deliver_event (session=0x5555560386d0, event=0x7ffff7c14128, tool=0x7fffffffbce0,
      file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1354
  torvalds#12 0x00005555557affaf in ordered_events__deliver_event (oe=0x555556038e60, event=0x555556135aa0) at util/session.c:132
  torvalds#13 0x00005555557bb605 in do_flush (oe=0x555556038e60, show_progress=false) at util/ordered-events.c:245
  torvalds#14 0x00005555557bb95c in __ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND, timestamp=0) at util/ordered-events.c:324
  torvalds#15 0x00005555557bba46 in ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND) at util/ordered-events.c:342
  torvalds#16 0x00005555557b1b3b in perf_event__process_finished_round (tool=0x7fffffffbce0, event=0x7ffff7c15bb8, oe=0x555556038e60)
      at util/session.c:780
  torvalds#17 0x00005555557b3b27 in perf_session__process_user_event (session=0x5555560386d0, event=0x7ffff7c15bb8, file_offset=117688,
      file_path=0x555556038ff0 "perf.data") at util/session.c:1406

As you can see the entry->ms.map was NULL even if he->ms.map has a
value.  This is because 'sym' sort key is not given, so it cannot assume
whether he->ms.sym and entry->ms.sym is the same.  I only checked the
'sym' sort key here as it implies 'dso' behavior (so maps are the same).

Fixes: ac01c8c ("perf hist: Update hist symbol when updating maps")
Signed-off-by: Namhyung Kim <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Matt Fleming <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
mj22226 pushed a commit to mj22226/linux that referenced this pull request Oct 15, 2024
commit ac01c8c upstream.

AddressSanitizer found a use-after-free bug in the symbol code which
manifested as 'perf top' segfaulting.

  ==1238389==ERROR: AddressSanitizer: heap-use-after-free on address 0x60b00c48844b at pc 0x5650d8035961 bp 0x7f751aaecc90 sp 0x7f751aaecc80
  READ of size 1 at 0x60b00c48844b thread T193
      #0 0x5650d8035960 in _sort__sym_cmp util/sort.c:310
      #1 0x5650d8043744 in hist_entry__cmp util/hist.c:1286
      #2 0x5650d8043951 in hists__findnew_entry util/hist.c:614
      #3 0x5650d804568f in __hists__add_entry util/hist.c:754
      #4 0x5650d8045bf9 in hists__add_entry util/hist.c:772
      #5 0x5650d8045df1 in iter_add_single_normal_entry util/hist.c:997
      torvalds#6 0x5650d8043326 in hist_entry_iter__add util/hist.c:1242
      torvalds#7 0x5650d7ceeefe in perf_event__process_sample /home/matt/src/linux/tools/perf/builtin-top.c:845
      torvalds#8 0x5650d7ceeefe in deliver_event /home/matt/src/linux/tools/perf/builtin-top.c:1208
      torvalds#9 0x5650d7fdb51b in do_flush util/ordered-events.c:245
      torvalds#10 0x5650d7fdb51b in __ordered_events__flush util/ordered-events.c:324
      torvalds#11 0x5650d7ced743 in process_thread /home/matt/src/linux/tools/perf/builtin-top.c:1120
      torvalds#12 0x7f757ef1f133 in start_thread nptl/pthread_create.c:442
      torvalds#13 0x7f757ef9f7db in clone3 ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81

When updating hist maps it's also necessary to update the hist symbol
reference because the old one gets freed in map__put().

While this bug was probably introduced with 5c24b67 ("perf
tools: Replace map->referenced & maps->removed_maps with map->refcnt"),
the symbol objects were leaked until c087e94 ("perf machine:
Fix refcount usage when processing PERF_RECORD_KSYMBOL") was merged so
the bug was masked.

Fixes: c087e94 ("perf machine: Fix refcount usage when processing PERF_RECORD_KSYMBOL")
Reported-by: Yunzhao Li <[email protected]>
Signed-off-by: Matt Fleming (Cloudflare) <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: [email protected]
Cc: Namhyung Kim <[email protected]>
Cc: Riccardo Mancini <[email protected]>
Cc: [email protected] # v5.13+
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
mj22226 pushed a commit to mj22226/linux that referenced this pull request Oct 15, 2024
commit 9af2efe upstream.

The fields in the hist_entry are filled on-demand which means they only
have meaningful values when relevant sort keys are used.

So if neither of 'dso' nor 'sym' sort keys are used, the map/symbols in
the hist entry can be garbage.  So it shouldn't access it
unconditionally.

I got a segfault, when I wanted to see cgroup profiles.

  $ sudo perf record -a --all-cgroups --synth=cgroup true

  $ sudo perf report -s cgroup

  Program received signal SIGSEGV, Segmentation fault.
  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  48		return RC_CHK_ACCESS(map)->dso;
  (gdb) bt
  #0  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  #1  0x00005555557aa39b in map__load (map=0x0) at util/map.c:344
  #2  0x00005555557aa592 in map__find_symbol (map=0x0, addr=140736115941088) at util/map.c:385
  #3  0x00005555557ef000 in hists__findnew_entry (hists=0x555556039d60, entry=0x7fffffffa4c0, al=0x7fffffffa8c0, sample_self=true)
      at util/hist.c:644
  #4  0x00005555557ef61c in __hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      block_info=0x0, sample=0x7fffffffaa90, sample_self=true, ops=0x0) at util/hist.c:761
  #5  0x00005555557ef71f in hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      sample=0x7fffffffaa90, sample_self=true) at util/hist.c:779
  torvalds#6  0x00005555557f00fb in iter_add_single_normal_entry (iter=0x7fffffffa900, al=0x7fffffffa8c0) at util/hist.c:1015
  torvalds#7  0x00005555557f09a7 in hist_entry_iter__add (iter=0x7fffffffa900, al=0x7fffffffa8c0, max_stack_depth=127, arg=0x7fffffffbce0)
      at util/hist.c:1260
  torvalds#8  0x00005555555ba7ce in process_sample_event (tool=0x7fffffffbce0, event=0x7ffff7c14128, sample=0x7fffffffaa90, evsel=0x555556039ad0,
      machine=0x5555560388e8) at builtin-report.c:334
  torvalds#9  0x00005555557b30c8 in evlist__deliver_sample (evlist=0x555556039010, tool=0x7fffffffbce0, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, evsel=0x555556039ad0, machine=0x5555560388e8) at util/session.c:1232
  torvalds#10 0x00005555557b32bc in machines__deliver_event (machines=0x5555560388e8, evlist=0x555556039010, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, tool=0x7fffffffbce0, file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1271
  torvalds#11 0x00005555557b3848 in perf_session__deliver_event (session=0x5555560386d0, event=0x7ffff7c14128, tool=0x7fffffffbce0,
      file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1354
  torvalds#12 0x00005555557affaf in ordered_events__deliver_event (oe=0x555556038e60, event=0x555556135aa0) at util/session.c:132
  torvalds#13 0x00005555557bb605 in do_flush (oe=0x555556038e60, show_progress=false) at util/ordered-events.c:245
  torvalds#14 0x00005555557bb95c in __ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND, timestamp=0) at util/ordered-events.c:324
  torvalds#15 0x00005555557bba46 in ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND) at util/ordered-events.c:342
  torvalds#16 0x00005555557b1b3b in perf_event__process_finished_round (tool=0x7fffffffbce0, event=0x7ffff7c15bb8, oe=0x555556038e60)
      at util/session.c:780
  torvalds#17 0x00005555557b3b27 in perf_session__process_user_event (session=0x5555560386d0, event=0x7ffff7c15bb8, file_offset=117688,
      file_path=0x555556038ff0 "perf.data") at util/session.c:1406

As you can see the entry->ms.map was NULL even if he->ms.map has a
value.  This is because 'sym' sort key is not given, so it cannot assume
whether he->ms.sym and entry->ms.sym is the same.  I only checked the
'sym' sort key here as it implies 'dso' behavior (so maps are the same).

Fixes: ac01c8c ("perf hist: Update hist symbol when updating maps")
Signed-off-by: Namhyung Kim <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Matt Fleming <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
staging-kernelci-org pushed a commit to kernelci/linux that referenced this pull request Oct 17, 2024
commit ac01c8c upstream.

AddressSanitizer found a use-after-free bug in the symbol code which
manifested as 'perf top' segfaulting.

  ==1238389==ERROR: AddressSanitizer: heap-use-after-free on address 0x60b00c48844b at pc 0x5650d8035961 bp 0x7f751aaecc90 sp 0x7f751aaecc80
  READ of size 1 at 0x60b00c48844b thread T193
      #0 0x5650d8035960 in _sort__sym_cmp util/sort.c:310
      #1 0x5650d8043744 in hist_entry__cmp util/hist.c:1286
      #2 0x5650d8043951 in hists__findnew_entry util/hist.c:614
      #3 0x5650d804568f in __hists__add_entry util/hist.c:754
      #4 0x5650d8045bf9 in hists__add_entry util/hist.c:772
      #5 0x5650d8045df1 in iter_add_single_normal_entry util/hist.c:997
      torvalds#6 0x5650d8043326 in hist_entry_iter__add util/hist.c:1242
      torvalds#7 0x5650d7ceeefe in perf_event__process_sample /home/matt/src/linux/tools/perf/builtin-top.c:845
      torvalds#8 0x5650d7ceeefe in deliver_event /home/matt/src/linux/tools/perf/builtin-top.c:1208
      torvalds#9 0x5650d7fdb51b in do_flush util/ordered-events.c:245
      torvalds#10 0x5650d7fdb51b in __ordered_events__flush util/ordered-events.c:324
      torvalds#11 0x5650d7ced743 in process_thread /home/matt/src/linux/tools/perf/builtin-top.c:1120
      torvalds#12 0x7f757ef1f133 in start_thread nptl/pthread_create.c:442
      torvalds#13 0x7f757ef9f7db in clone3 ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81

When updating hist maps it's also necessary to update the hist symbol
reference because the old one gets freed in map__put().

While this bug was probably introduced with 5c24b67 ("perf
tools: Replace map->referenced & maps->removed_maps with map->refcnt"),
the symbol objects were leaked until c087e94 ("perf machine:
Fix refcount usage when processing PERF_RECORD_KSYMBOL") was merged so
the bug was masked.

Fixes: c087e94 ("perf machine: Fix refcount usage when processing PERF_RECORD_KSYMBOL")
Reported-by: Yunzhao Li <[email protected]>
Signed-off-by: Matt Fleming (Cloudflare) <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: [email protected]
Cc: Namhyung Kim <[email protected]>
Cc: Riccardo Mancini <[email protected]>
Cc: [email protected] # v5.13+
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
staging-kernelci-org pushed a commit to kernelci/linux that referenced this pull request Oct 17, 2024
commit 9af2efe upstream.

The fields in the hist_entry are filled on-demand which means they only
have meaningful values when relevant sort keys are used.

So if neither of 'dso' nor 'sym' sort keys are used, the map/symbols in
the hist entry can be garbage.  So it shouldn't access it
unconditionally.

I got a segfault, when I wanted to see cgroup profiles.

  $ sudo perf record -a --all-cgroups --synth=cgroup true

  $ sudo perf report -s cgroup

  Program received signal SIGSEGV, Segmentation fault.
  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  48		return RC_CHK_ACCESS(map)->dso;
  (gdb) bt
  #0  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  #1  0x00005555557aa39b in map__load (map=0x0) at util/map.c:344
  #2  0x00005555557aa592 in map__find_symbol (map=0x0, addr=140736115941088) at util/map.c:385
  #3  0x00005555557ef000 in hists__findnew_entry (hists=0x555556039d60, entry=0x7fffffffa4c0, al=0x7fffffffa8c0, sample_self=true)
      at util/hist.c:644
  #4  0x00005555557ef61c in __hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      block_info=0x0, sample=0x7fffffffaa90, sample_self=true, ops=0x0) at util/hist.c:761
  #5  0x00005555557ef71f in hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      sample=0x7fffffffaa90, sample_self=true) at util/hist.c:779
  torvalds#6  0x00005555557f00fb in iter_add_single_normal_entry (iter=0x7fffffffa900, al=0x7fffffffa8c0) at util/hist.c:1015
  torvalds#7  0x00005555557f09a7 in hist_entry_iter__add (iter=0x7fffffffa900, al=0x7fffffffa8c0, max_stack_depth=127, arg=0x7fffffffbce0)
      at util/hist.c:1260
  torvalds#8  0x00005555555ba7ce in process_sample_event (tool=0x7fffffffbce0, event=0x7ffff7c14128, sample=0x7fffffffaa90, evsel=0x555556039ad0,
      machine=0x5555560388e8) at builtin-report.c:334
  torvalds#9  0x00005555557b30c8 in evlist__deliver_sample (evlist=0x555556039010, tool=0x7fffffffbce0, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, evsel=0x555556039ad0, machine=0x5555560388e8) at util/session.c:1232
  torvalds#10 0x00005555557b32bc in machines__deliver_event (machines=0x5555560388e8, evlist=0x555556039010, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, tool=0x7fffffffbce0, file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1271
  torvalds#11 0x00005555557b3848 in perf_session__deliver_event (session=0x5555560386d0, event=0x7ffff7c14128, tool=0x7fffffffbce0,
      file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1354
  torvalds#12 0x00005555557affaf in ordered_events__deliver_event (oe=0x555556038e60, event=0x555556135aa0) at util/session.c:132
  torvalds#13 0x00005555557bb605 in do_flush (oe=0x555556038e60, show_progress=false) at util/ordered-events.c:245
  torvalds#14 0x00005555557bb95c in __ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND, timestamp=0) at util/ordered-events.c:324
  torvalds#15 0x00005555557bba46 in ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND) at util/ordered-events.c:342
  torvalds#16 0x00005555557b1b3b in perf_event__process_finished_round (tool=0x7fffffffbce0, event=0x7ffff7c15bb8, oe=0x555556038e60)
      at util/session.c:780
  torvalds#17 0x00005555557b3b27 in perf_session__process_user_event (session=0x5555560386d0, event=0x7ffff7c15bb8, file_offset=117688,
      file_path=0x555556038ff0 "perf.data") at util/session.c:1406

As you can see the entry->ms.map was NULL even if he->ms.map has a
value.  This is because 'sym' sort key is not given, so it cannot assume
whether he->ms.sym and entry->ms.sym is the same.  I only checked the
'sym' sort key here as it implies 'dso' behavior (so maps are the same).

Fixes: ac01c8c ("perf hist: Update hist symbol when updating maps")
Signed-off-by: Namhyung Kim <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Matt Fleming <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
1054009064 pushed a commit to 1054009064/linux that referenced this pull request Oct 17, 2024
commit ac01c8c upstream.

AddressSanitizer found a use-after-free bug in the symbol code which
manifested as 'perf top' segfaulting.

  ==1238389==ERROR: AddressSanitizer: heap-use-after-free on address 0x60b00c48844b at pc 0x5650d8035961 bp 0x7f751aaecc90 sp 0x7f751aaecc80
  READ of size 1 at 0x60b00c48844b thread T193
      #0 0x5650d8035960 in _sort__sym_cmp util/sort.c:310
      #1 0x5650d8043744 in hist_entry__cmp util/hist.c:1286
      #2 0x5650d8043951 in hists__findnew_entry util/hist.c:614
      #3 0x5650d804568f in __hists__add_entry util/hist.c:754
      #4 0x5650d8045bf9 in hists__add_entry util/hist.c:772
      #5 0x5650d8045df1 in iter_add_single_normal_entry util/hist.c:997
      torvalds#6 0x5650d8043326 in hist_entry_iter__add util/hist.c:1242
      torvalds#7 0x5650d7ceeefe in perf_event__process_sample /home/matt/src/linux/tools/perf/builtin-top.c:845
      torvalds#8 0x5650d7ceeefe in deliver_event /home/matt/src/linux/tools/perf/builtin-top.c:1208
      torvalds#9 0x5650d7fdb51b in do_flush util/ordered-events.c:245
      torvalds#10 0x5650d7fdb51b in __ordered_events__flush util/ordered-events.c:324
      torvalds#11 0x5650d7ced743 in process_thread /home/matt/src/linux/tools/perf/builtin-top.c:1120
      torvalds#12 0x7f757ef1f133 in start_thread nptl/pthread_create.c:442
      torvalds#13 0x7f757ef9f7db in clone3 ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81

When updating hist maps it's also necessary to update the hist symbol
reference because the old one gets freed in map__put().

While this bug was probably introduced with 5c24b67 ("perf
tools: Replace map->referenced & maps->removed_maps with map->refcnt"),
the symbol objects were leaked until c087e94 ("perf machine:
Fix refcount usage when processing PERF_RECORD_KSYMBOL") was merged so
the bug was masked.

Fixes: c087e94 ("perf machine: Fix refcount usage when processing PERF_RECORD_KSYMBOL")
Reported-by: Yunzhao Li <[email protected]>
Signed-off-by: Matt Fleming (Cloudflare) <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: [email protected]
Cc: Namhyung Kim <[email protected]>
Cc: Riccardo Mancini <[email protected]>
Cc: [email protected] # v5.13+
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
1054009064 pushed a commit to 1054009064/linux that referenced this pull request Oct 17, 2024
commit 9af2efe upstream.

The fields in the hist_entry are filled on-demand which means they only
have meaningful values when relevant sort keys are used.

So if neither of 'dso' nor 'sym' sort keys are used, the map/symbols in
the hist entry can be garbage.  So it shouldn't access it
unconditionally.

I got a segfault, when I wanted to see cgroup profiles.

  $ sudo perf record -a --all-cgroups --synth=cgroup true

  $ sudo perf report -s cgroup

  Program received signal SIGSEGV, Segmentation fault.
  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  48		return RC_CHK_ACCESS(map)->dso;
  (gdb) bt
  #0  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  #1  0x00005555557aa39b in map__load (map=0x0) at util/map.c:344
  #2  0x00005555557aa592 in map__find_symbol (map=0x0, addr=140736115941088) at util/map.c:385
  #3  0x00005555557ef000 in hists__findnew_entry (hists=0x555556039d60, entry=0x7fffffffa4c0, al=0x7fffffffa8c0, sample_self=true)
      at util/hist.c:644
  #4  0x00005555557ef61c in __hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      block_info=0x0, sample=0x7fffffffaa90, sample_self=true, ops=0x0) at util/hist.c:761
  #5  0x00005555557ef71f in hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      sample=0x7fffffffaa90, sample_self=true) at util/hist.c:779
  torvalds#6  0x00005555557f00fb in iter_add_single_normal_entry (iter=0x7fffffffa900, al=0x7fffffffa8c0) at util/hist.c:1015
  torvalds#7  0x00005555557f09a7 in hist_entry_iter__add (iter=0x7fffffffa900, al=0x7fffffffa8c0, max_stack_depth=127, arg=0x7fffffffbce0)
      at util/hist.c:1260
  torvalds#8  0x00005555555ba7ce in process_sample_event (tool=0x7fffffffbce0, event=0x7ffff7c14128, sample=0x7fffffffaa90, evsel=0x555556039ad0,
      machine=0x5555560388e8) at builtin-report.c:334
  torvalds#9  0x00005555557b30c8 in evlist__deliver_sample (evlist=0x555556039010, tool=0x7fffffffbce0, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, evsel=0x555556039ad0, machine=0x5555560388e8) at util/session.c:1232
  torvalds#10 0x00005555557b32bc in machines__deliver_event (machines=0x5555560388e8, evlist=0x555556039010, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, tool=0x7fffffffbce0, file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1271
  torvalds#11 0x00005555557b3848 in perf_session__deliver_event (session=0x5555560386d0, event=0x7ffff7c14128, tool=0x7fffffffbce0,
      file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1354
  torvalds#12 0x00005555557affaf in ordered_events__deliver_event (oe=0x555556038e60, event=0x555556135aa0) at util/session.c:132
  torvalds#13 0x00005555557bb605 in do_flush (oe=0x555556038e60, show_progress=false) at util/ordered-events.c:245
  torvalds#14 0x00005555557bb95c in __ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND, timestamp=0) at util/ordered-events.c:324
  torvalds#15 0x00005555557bba46 in ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND) at util/ordered-events.c:342
  torvalds#16 0x00005555557b1b3b in perf_event__process_finished_round (tool=0x7fffffffbce0, event=0x7ffff7c15bb8, oe=0x555556038e60)
      at util/session.c:780
  torvalds#17 0x00005555557b3b27 in perf_session__process_user_event (session=0x5555560386d0, event=0x7ffff7c15bb8, file_offset=117688,
      file_path=0x555556038ff0 "perf.data") at util/session.c:1406

As you can see the entry->ms.map was NULL even if he->ms.map has a
value.  This is because 'sym' sort key is not given, so it cannot assume
whether he->ms.sym and entry->ms.sym is the same.  I only checked the
'sym' sort key here as it implies 'dso' behavior (so maps are the same).

Fixes: ac01c8c ("perf hist: Update hist symbol when updating maps")
Signed-off-by: Namhyung Kim <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Matt Fleming <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
yhamamachi pushed a commit to yhamamachi/linux-pcie-virtio-net that referenced this pull request Oct 23, 2024
We shouldn't set real_dev to NULL because packets can be in transit and
xfrm might call xdo_dev_offload_ok() in parallel. All callbacks assume
real_dev is set.

 Example trace:
 kernel: BUG: unable to handle page fault for address: 0000000000001030
 kernel: bond0: (slave eni0np1): making interface the new active one
 kernel: #PF: supervisor write access in kernel mode
 kernel: #PF: error_code(0x0002) - not-present page
 kernel: PGD 0 P4D 0
 kernel: Oops: 0002 [#1] PREEMPT SMP
 kernel: CPU: 4 PID: 2237 Comm: ping Not tainted 6.7.7+ torvalds#12
 kernel: Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-2.fc40 04/01/2014
 kernel: RIP: 0010:nsim_ipsec_offload_ok+0xc/0x20 [netdevsim]
 kernel: bond0: (slave eni0np1): bond_ipsec_add_sa_all: failed to add SA
 kernel: Code: e0 0f 0b 48 83 7f 38 00 74 de 0f 0b 48 8b 47 08 48 8b 37 48 8b 78 40 e9 b2 e5 9a d7 66 90 0f 1f 44 00 00 48 8b 86 80 02 00 00 <83> 80 30 10 00 00 01 b8 01 00 00 00 c3 0f 1f 80 00 00 00 00 0f 1f
 kernel: bond0: (slave eni0np1): making interface the new active one
 kernel: RSP: 0018:ffffabde81553b98 EFLAGS: 00010246
 kernel: bond0: (slave eni0np1): bond_ipsec_add_sa_all: failed to add SA
 kernel:
 kernel: RAX: 0000000000000000 RBX: ffff9eb404e74900 RCX: ffff9eb403d97c60
 kernel: RDX: ffffffffc090de10 RSI: ffff9eb404e74900 RDI: ffff9eb3c5de9e00
 kernel: RBP: ffff9eb3c0a42000 R08: 0000000000000010 R09: 0000000000000014
 kernel: R10: 7974203030303030 R11: 3030303030303030 R12: 0000000000000000
 kernel: R13: ffff9eb3c5de9e00 R14: ffffabde81553cc8 R15: ffff9eb404c53000
 kernel: FS:  00007f2a77a3ad00(0000) GS:ffff9eb43bd00000(0000) knlGS:0000000000000000
 kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 kernel: CR2: 0000000000001030 CR3: 00000001122ab000 CR4: 0000000000350ef0
 kernel: bond0: (slave eni0np1): making interface the new active one
 kernel: Call Trace:
 kernel:  <TASK>
 kernel:  ? __die+0x1f/0x60
 kernel: bond0: (slave eni0np1): bond_ipsec_add_sa_all: failed to add SA
 kernel:  ? page_fault_oops+0x142/0x4c0
 kernel:  ? do_user_addr_fault+0x65/0x670
 kernel:  ? kvm_read_and_reset_apf_flags+0x3b/0x50
 kernel: bond0: (slave eni0np1): making interface the new active one
 kernel:  ? exc_page_fault+0x7b/0x180
 kernel:  ? asm_exc_page_fault+0x22/0x30
 kernel:  ? nsim_bpf_uninit+0x50/0x50 [netdevsim]
 kernel: bond0: (slave eni0np1): bond_ipsec_add_sa_all: failed to add SA
 kernel:  ? nsim_ipsec_offload_ok+0xc/0x20 [netdevsim]
 kernel: bond0: (slave eni0np1): making interface the new active one
 kernel:  bond_ipsec_offload_ok+0x7b/0x90 [bonding]
 kernel:  xfrm_output+0x61/0x3b0
 kernel: bond0: (slave eni0np1): bond_ipsec_add_sa_all: failed to add SA
 kernel:  ip_push_pending_frames+0x56/0x80

Fixes: 18cb261 ("bonding: support hardware encryption offload to slaves")
Signed-off-by: Nikolay Aleksandrov <[email protected]>
Reviewed-by: Hangbin Liu <[email protected]>
Signed-off-by: Paolo Abeni <[email protected]>
yhamamachi pushed a commit to yhamamachi/linux-pcie-virtio-net that referenced this pull request Oct 23, 2024
A sysfs reader can race with a device reset or removal, attempting to
read device state when the device is not actually present. eg:

     [exception RIP: qed_get_current_link+17]
  torvalds#8 [ffffb9e4f2907c48] qede_get_link_ksettings at ffffffffc07a994a [qede]
  torvalds#9 [ffffb9e4f2907cd8] __rh_call_get_link_ksettings at ffffffff992b01a3
 torvalds#10 [ffffb9e4f2907d38] __ethtool_get_link_ksettings at ffffffff992b04e4
 torvalds#11 [ffffb9e4f2907d90] duplex_show at ffffffff99260300
 torvalds#12 [ffffb9e4f2907e38] dev_attr_show at ffffffff9905a01c
 torvalds#13 [ffffb9e4f2907e50] sysfs_kf_seq_show at ffffffff98e0145b
 torvalds#14 [ffffb9e4f2907e68] seq_read at ffffffff98d902e3
 torvalds#15 [ffffb9e4f2907ec8] vfs_read at ffffffff98d657d1
 torvalds#16 [ffffb9e4f2907f00] ksys_read at ffffffff98d65c3f
 torvalds#17 [ffffb9e4f2907f38] do_syscall_64 at ffffffff98a052fb

 crash> struct net_device.state ffff9a9d21336000
    state = 5,

state 5 is __LINK_STATE_START (0b1) and __LINK_STATE_NOCARRIER (0b100).
The device is not present, note lack of __LINK_STATE_PRESENT (0b10).

This is the same sort of panic as observed in commit 4224cfd
("net-sysfs: add check for netdevice being present to speed_show").

There are many other callers of __ethtool_get_link_ksettings() which
don't have a device presence check.

Move this check into ethtool to protect all callers.

Fixes: d519e17 ("net: export device speed and duplex via sysfs")
Fixes: 4224cfd ("net-sysfs: add check for netdevice being present to speed_show")
Signed-off-by: Jamie Bainbridge <[email protected]>
Link: https://patch.msgid.link/8bae218864beaa44ed01628140475b9bf641c5b0.1724393671.git.jamie.bainbridge@gmail.com
Signed-off-by: Jakub Kicinski <[email protected]>
kuba-moo added a commit to linux-netdev/testing that referenced this pull request Oct 31, 2024
Daniel Machon says:

====================
net: sparx5: add support for lan969x switch device

== Description:

This series is the second of a multi-part series, that prepares and adds
support for the new lan969x switch driver.

The upstreaming efforts is split into multiple series (might change a
bit as we go along):

        1) Prepare the Sparx5 driver for lan969x (merged)

    --> 2) add support lan969x (same basic features as Sparx5
           provides excl. FDMA and VCAP).

        3) Add support for lan969x VCAP, FDMA and RGMII

== Lan969x in short:

The lan969x Ethernet switch family [1] provides a rich set of
switching features and port configurations (up to 30 ports) from 10Mbps
to 10Gbps, with support for RGMII, SGMII, QSGMII, USGMII, and USXGMII,
ideal for industrial & process automation infrastructure applications,
transport, grid automation, power substation automation, and ring &
intra-ring topologies. The LAN969x family is hardware and software
compatible and scalable supporting 46Gbps to 102Gbps switch bandwidths.

== Preparing Sparx5 for lan969x:

The main preparation work for lan969x has already been merged [1].

After this series is applied, lan969x will have the same functionality
as Sparx5, except for VCAP and FDMA support. QoS features that requires
the VCAP (e.g. PSFP, port mirroring) will obviously not work until VCAP
support is added later.

== Patch breakdown:

Patch #1-#4  do some preparation work for lan969x

Patch #5     adds new registers required by lan969x

Patch torvalds#6     adds initial match data for all lan969x targets

Patch torvalds#7     defines the lan969x register differences

Patch torvalds#8     adds lan969x constants to match data

Patch torvalds#9     adds some lan969x ops in bulk

Patch torvalds#10    adds PTP function to ops

Patch torvalds#11    adds lan969x_calendar.c for calculating the calendar

Patch torvalds#12    makes additional use of the is_sparx5() macro to branch out
             in certain places.

Patch torvalds#13    documents lan969x in the dt-bindings

Patch torvalds#14    adds lan969x compatible string to sparx5 driver

Patch torvalds#15    introduces new concept of per-target features

[1] https://lore.kernel.org/netdev/20241004-b4-sparx5-lan969x-switch-driver-v2-0-d3290f581663@microchip.com/

v1: https://lore.kernel.org/20241021-sparx5-lan969x-switch-driver-2-v1-0-c8c49ef21e0f@microchip.com
====================

Link: https://patch.msgid.link/20241024-sparx5-lan969x-switch-driver-2-v2-0-a0b5fae88a0f@microchip.com
Signed-off-by: Jakub Kicinski <[email protected]>
intel-lab-lkp pushed a commit to intel-lab-lkp/linux that referenced this pull request Nov 1, 2024
Dennis reports a boot crash on recent Lenovo laptops with a USB4 dock.

Since commit 0fc7088 ("thunderbolt: Reset USB4 v2 host router") and
commit 59a54c5 ("thunderbolt: Reset topology created by the boot
firmware"), USB4 v2 and v1 Host Routers are reset on probe of the
thunderbolt driver.

The reset clears the Presence Detect State and Data Link Layer Link Active
bits at the USB4 Host Router's Root Port and thus causes hot removal of the
dock.

The crash occurs when pciehp is unbound from one of the dock's Downstream
Ports:  pciehp creates a pci_slot on bind and destroys it on unbind.  The
pci_slot contains a pointer to the pci_bus below the Downstream Port, but
a reference on that pci_bus is never acquired.  The pci_bus is destroyed
before the pci_slot, so a use-after-free ensues when pci_slot_release()
accesses slot->bus.

In principle this should not happen because pci_stop_bus_device() unbinds
pciehp (and therefore destroys the pci_slot) before the pci_bus is
destroyed by pci_remove_bus_device().

However the stacktrace provided by Dennis shows that pciehp is unbound from
pci_remove_bus_device() instead of pci_stop_bus_device().  To understand
the significance of this, one needs to know that the PCI core uses a two
step process to remove a portion of the hierarchy:  It first unbinds all
drivers in the sub-hierarchy in pci_stop_bus_device() and then actually
removes the devices in pci_remove_bus_device().  There is no precaution to
prevent driver binding in-between pci_stop_bus_device() and
pci_remove_bus_device().

In Dennis' case, it seems removal of the hierarchy by pciehp races with
driver binding by pci_bus_add_devices().  pciehp is bound to the
Downstream Port after pci_stop_bus_device() has run, so it is unbound by
pci_remove_bus_device() instead of pci_stop_bus_device().  Because the
pci_bus has already been destroyed at that point, accesses to it result in
a use-after-free.

One might conclude that driver binding needs to be prevented after
pci_stop_bus_device() has run.  However it seems risky that pci_slot points
to pci_bus without holding a reference.  Solely relying on correct ordering
of driver unbind versus pci_bus destruction is certainly not defensive
programming.

If pci_slot has a need to access data in pci_bus, it ought to acquire a
reference.  Amend pci_create_slot() accordingly.  Dennis reports that the
crash is not reproducible with this change.

Abridged stacktrace:

  pcieport 0000:00:07.0: PME: Signaling with IRQ 156
  pcieport 0000:00:07.0: pciehp: Slot torvalds#12 AttnBtn- PwrCtrl- MRL- AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis- LLActRep+
  pci_bus 0000:20: dev 00, created physical slot 12
  pcieport 0000:00:07.0: pciehp: Slot(12): Card not present
  ...
  pcieport 0000:21:02.0: pciehp: pcie_disable_notification: SLOTCTRL d8 write cmd 0
  Oops: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b6b: 0000 [#1] PREEMPT SMP NOPTI
  CPU: 13 UID: 0 PID: 134 Comm: irq/156-pciehp Not tainted 6.11.0-devel+ #1
  RIP: 0010:dev_driver_string+0x12/0x40
  pci_destroy_slot
  pciehp_remove
  pcie_port_remove_service
  device_release_driver_internal
  bus_remove_device
  device_del
  device_unregister
  remove_iter
  device_for_each_child
  pcie_portdrv_remove
  pci_device_remove
  device_release_driver_internal
  bus_remove_device
  device_del
  pci_remove_bus_device (recursive invocation)
  pci_remove_bus_device
  pciehp_unconfigure_device
  pciehp_disable_slot
  pciehp_handle_presence_or_link_change
  pciehp_ist

Link: https://lore.kernel.org/r/4bfd4c0e976c1776cd08e76603903b338cf25729.1728579288.git.lukas@wunner.de
Reported-by: Dennis Wassenberg <[email protected]>
Closes: https://lore.kernel.org/r/[email protected]/
Tested-by: Dennis Wassenberg <[email protected]>
Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Mika Westerberg <[email protected]>
Cc: [email protected]
intel-lab-lkp pushed a commit to intel-lab-lkp/linux that referenced this pull request Nov 4, 2024
…buckets_create

Commit b035f5a ("mm: slab: reduce the kmalloc() minimum alignment
if DMA bouncing possible") reduced ARCH_KMALLOC_MINALIGN to 8 on arm64.
However, with KASAN_HW_TAGS enabled, arch_slab_minalign() becomes 16.
This causes kmalloc_caches[*][8] to be aliased to kmalloc_caches[*][16],
resulting in kmem_buckets_create() attempting to create a kmem_cache for
size 16 twice. This duplication triggers warnings on boot:

[    2.325108] ------------[ cut here ]------------
[    2.325135] kmem_cache of name 'memdup_user-16' already exists
[    2.325783] WARNING: CPU: 0 PID: 1 at mm/slab_common.c:107 __kmem_cache_create_args+0xb8/0x3b0
[    2.327957] Modules linked in:
[    2.328550] CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.12.0-rc5mm-unstable-arm64+ torvalds#12
[    2.328683] Hardware name: QEMU QEMU Virtual Machine, BIOS 2024.02-2 03/11/2024
[    2.328790] pstate: 61000009 (nZCv daif -PAN -UAO -TCO +DIT -SSBS BTYPE=--)
[    2.328911] pc : __kmem_cache_create_args+0xb8/0x3b0
[    2.328930] lr : __kmem_cache_create_args+0xb8/0x3b0
[    2.328942] sp : ffff800083d6fc50
[    2.328961] x29: ffff800083d6fc50 x28: f2ff0000c1674410 x27: ffff8000820b0598
[    2.329061] x26: 000000007fffffff x25: 0000000000000010 x24: 0000000000002000
[    2.329101] x23: ffff800083d6fce8 x22: ffff8000832222e8 x21: ffff800083222388
[    2.329118] x20: f2ff0000c1674410 x19: f5ff0000c16364c0 x18: ffff800083d80030
[    2.329135] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
[    2.329152] x14: 0000000000000000 x13: 0a73747369786520 x12: 79646165726c6120
[    2.329169] x11: 656820747563205b x10: 2d2d2d2d2d2d2d2d x9 : 0000000000000000
[    2.329194] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
[    2.329210] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000
[    2.329226] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
[    2.329291] Call trace:
[    2.329407]  __kmem_cache_create_args+0xb8/0x3b0
[    2.329499]  kmem_buckets_create+0xfc/0x320
[    2.329526]  init_user_buckets+0x34/0x78
[    2.329540]  do_one_initcall+0x64/0x3c8
[    2.329550]  kernel_init_freeable+0x26c/0x578
[    2.329562]  kernel_init+0x3c/0x258
[    2.329574]  ret_from_fork+0x10/0x20
[    2.329698] ---[ end trace 0000000000000000 ]---

[    2.403704] ------------[ cut here ]------------
[    2.404716] kmem_cache of name 'msg_msg-16' already exists
[    2.404801] WARNING: CPU: 2 PID: 1 at mm/slab_common.c:107 __kmem_cache_create_args+0xb8/0x3b0
[    2.404842] Modules linked in:
[    2.404971] CPU: 2 UID: 0 PID: 1 Comm: swapper/0 Tainted: G        W          6.12.0-rc5mm-unstable-arm64+ torvalds#12
[    2.405026] Tainted: [W]=WARN
[    2.405043] Hardware name: QEMU QEMU Virtual Machine, BIOS 2024.02-2 03/11/2024
[    2.405057] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[    2.405079] pc : __kmem_cache_create_args+0xb8/0x3b0
[    2.405100] lr : __kmem_cache_create_args+0xb8/0x3b0
[    2.405111] sp : ffff800083d6fc50
[    2.405115] x29: ffff800083d6fc50 x28: fbff0000c1674410 x27: ffff8000820b0598
[    2.405135] x26: 000000000000ffd0 x25: 0000000000000010 x24: 0000000000006000
[    2.405153] x23: ffff800083d6fce8 x22: ffff8000832222e8 x21: ffff800083222388
[    2.405169] x20: fbff0000c1674410 x19: fdff0000c163d6c0 x18: ffff800083d80030
[    2.405185] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
[    2.405201] x14: 0000000000000000 x13: 0a73747369786520 x12: 79646165726c6120
[    2.405217] x11: 656820747563205b x10: 2d2d2d2d2d2d2d2d x9 : 0000000000000000
[    2.405233] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
[    2.405248] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000
[    2.405271] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
[    2.405287] Call trace:
[    2.405293]  __kmem_cache_create_args+0xb8/0x3b0
[    2.405305]  kmem_buckets_create+0xfc/0x320
[    2.405315]  init_msg_buckets+0x34/0x78
[    2.405326]  do_one_initcall+0x64/0x3c8
[    2.405337]  kernel_init_freeable+0x26c/0x578
[    2.405348]  kernel_init+0x3c/0x258
[    2.405360]  ret_from_fork+0x10/0x20
[    2.405370] ---[ end trace 0000000000000000 ]---

To address this, alias kmem_cache for sizes smaller than min alignment
to the aligned sized kmem_cache, as done with the default system kmalloc
bucket.

Cc: <[email protected]> # 6.11.x
Fixes: b32801d ("mm/slab: Introduce kmem_buckets_create() and family")
Signed-off-by: Koichiro Den <[email protected]>
intel-lab-lkp pushed a commit to intel-lab-lkp/linux that referenced this pull request Nov 5, 2024
…buckets_create

Commit b035f5a ("mm: slab: reduce the kmalloc() minimum alignment
if DMA bouncing possible") reduced ARCH_KMALLOC_MINALIGN to 8 on arm64.
However, with KASAN_HW_TAGS enabled, arch_slab_minalign() becomes 16.
This causes kmalloc_caches[*][8] to be aliased to kmalloc_caches[*][16],
resulting in kmem_buckets_create() attempting to create a kmem_cache for
size 16 twice. This duplication triggers warnings on boot:

[    2.325108] ------------[ cut here ]------------
[    2.325135] kmem_cache of name 'memdup_user-16' already exists
[    2.325783] WARNING: CPU: 0 PID: 1 at mm/slab_common.c:107 __kmem_cache_create_args+0xb8/0x3b0
[    2.327957] Modules linked in:
[    2.328550] CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.12.0-rc5mm-unstable-arm64+ torvalds#12
[    2.328683] Hardware name: QEMU QEMU Virtual Machine, BIOS 2024.02-2 03/11/2024
[    2.328790] pstate: 61000009 (nZCv daif -PAN -UAO -TCO +DIT -SSBS BTYPE=--)
[    2.328911] pc : __kmem_cache_create_args+0xb8/0x3b0
[    2.328930] lr : __kmem_cache_create_args+0xb8/0x3b0
[    2.328942] sp : ffff800083d6fc50
[    2.328961] x29: ffff800083d6fc50 x28: f2ff0000c1674410 x27: ffff8000820b0598
[    2.329061] x26: 000000007fffffff x25: 0000000000000010 x24: 0000000000002000
[    2.329101] x23: ffff800083d6fce8 x22: ffff8000832222e8 x21: ffff800083222388
[    2.329118] x20: f2ff0000c1674410 x19: f5ff0000c16364c0 x18: ffff800083d80030
[    2.329135] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
[    2.329152] x14: 0000000000000000 x13: 0a73747369786520 x12: 79646165726c6120
[    2.329169] x11: 656820747563205b x10: 2d2d2d2d2d2d2d2d x9 : 0000000000000000
[    2.329194] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
[    2.329210] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000
[    2.329226] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
[    2.329291] Call trace:
[    2.329407]  __kmem_cache_create_args+0xb8/0x3b0
[    2.329499]  kmem_buckets_create+0xfc/0x320
[    2.329526]  init_user_buckets+0x34/0x78
[    2.329540]  do_one_initcall+0x64/0x3c8
[    2.329550]  kernel_init_freeable+0x26c/0x578
[    2.329562]  kernel_init+0x3c/0x258
[    2.329574]  ret_from_fork+0x10/0x20
[    2.329698] ---[ end trace 0000000000000000 ]---

[    2.403704] ------------[ cut here ]------------
[    2.404716] kmem_cache of name 'msg_msg-16' already exists
[    2.404801] WARNING: CPU: 2 PID: 1 at mm/slab_common.c:107 __kmem_cache_create_args+0xb8/0x3b0
[    2.404842] Modules linked in:
[    2.404971] CPU: 2 UID: 0 PID: 1 Comm: swapper/0 Tainted: G        W          6.12.0-rc5mm-unstable-arm64+ torvalds#12
[    2.405026] Tainted: [W]=WARN
[    2.405043] Hardware name: QEMU QEMU Virtual Machine, BIOS 2024.02-2 03/11/2024
[    2.405057] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[    2.405079] pc : __kmem_cache_create_args+0xb8/0x3b0
[    2.405100] lr : __kmem_cache_create_args+0xb8/0x3b0
[    2.405111] sp : ffff800083d6fc50
[    2.405115] x29: ffff800083d6fc50 x28: fbff0000c1674410 x27: ffff8000820b0598
[    2.405135] x26: 000000000000ffd0 x25: 0000000000000010 x24: 0000000000006000
[    2.405153] x23: ffff800083d6fce8 x22: ffff8000832222e8 x21: ffff800083222388
[    2.405169] x20: fbff0000c1674410 x19: fdff0000c163d6c0 x18: ffff800083d80030
[    2.405185] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
[    2.405201] x14: 0000000000000000 x13: 0a73747369786520 x12: 79646165726c6120
[    2.405217] x11: 656820747563205b x10: 2d2d2d2d2d2d2d2d x9 : 0000000000000000
[    2.405233] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
[    2.405248] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000
[    2.405271] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
[    2.405287] Call trace:
[    2.405293]  __kmem_cache_create_args+0xb8/0x3b0
[    2.405305]  kmem_buckets_create+0xfc/0x320
[    2.405315]  init_msg_buckets+0x34/0x78
[    2.405326]  do_one_initcall+0x64/0x3c8
[    2.405337]  kernel_init_freeable+0x26c/0x578
[    2.405348]  kernel_init+0x3c/0x258
[    2.405360]  ret_from_fork+0x10/0x20
[    2.405370] ---[ end trace 0000000000000000 ]---

To address this, alias kmem_cache for sizes smaller than min alignment
to the aligned sized kmem_cache, as done with the default system kmalloc
bucket.

Cc: <[email protected]> # 6.11.x
Fixes: b32801d ("mm/slab: Introduce kmem_buckets_create() and family")
Signed-off-by: Koichiro Den <[email protected]>
mj22226 pushed a commit to mj22226/linux that referenced this pull request Nov 6, 2024
…buckets_create

Commit b035f5a ("mm: slab: reduce the kmalloc() minimum alignment
if DMA bouncing possible") reduced ARCH_KMALLOC_MINALIGN to 8 on arm64.
However, with KASAN_HW_TAGS enabled, arch_slab_minalign() becomes 16.
This causes kmalloc_caches[*][8] to be aliased to kmalloc_caches[*][16],
resulting in kmem_buckets_create() attempting to create a kmem_cache for
size 16 twice. This duplication triggers warnings on boot:

[    2.325108] ------------[ cut here ]------------
[    2.325135] kmem_cache of name 'memdup_user-16' already exists
[    2.325783] WARNING: CPU: 0 PID: 1 at mm/slab_common.c:107 __kmem_cache_create_args+0xb8/0x3b0
[    2.327957] Modules linked in:
[    2.328550] CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.12.0-rc5mm-unstable-arm64+ torvalds#12
[    2.328683] Hardware name: QEMU QEMU Virtual Machine, BIOS 2024.02-2 03/11/2024
[    2.328790] pstate: 61000009 (nZCv daif -PAN -UAO -TCO +DIT -SSBS BTYPE=--)
[    2.328911] pc : __kmem_cache_create_args+0xb8/0x3b0
[    2.328930] lr : __kmem_cache_create_args+0xb8/0x3b0
[    2.328942] sp : ffff800083d6fc50
[    2.328961] x29: ffff800083d6fc50 x28: f2ff0000c1674410 x27: ffff8000820b0598
[    2.329061] x26: 000000007fffffff x25: 0000000000000010 x24: 0000000000002000
[    2.329101] x23: ffff800083d6fce8 x22: ffff8000832222e8 x21: ffff800083222388
[    2.329118] x20: f2ff0000c1674410 x19: f5ff0000c16364c0 x18: ffff800083d80030
[    2.329135] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
[    2.329152] x14: 0000000000000000 x13: 0a73747369786520 x12: 79646165726c6120
[    2.329169] x11: 656820747563205b x10: 2d2d2d2d2d2d2d2d x9 : 0000000000000000
[    2.329194] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
[    2.329210] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000
[    2.329226] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
[    2.329291] Call trace:
[    2.329407]  __kmem_cache_create_args+0xb8/0x3b0
[    2.329499]  kmem_buckets_create+0xfc/0x320
[    2.329526]  init_user_buckets+0x34/0x78
[    2.329540]  do_one_initcall+0x64/0x3c8
[    2.329550]  kernel_init_freeable+0x26c/0x578
[    2.329562]  kernel_init+0x3c/0x258
[    2.329574]  ret_from_fork+0x10/0x20
[    2.329698] ---[ end trace 0000000000000000 ]---

[    2.403704] ------------[ cut here ]------------
[    2.404716] kmem_cache of name 'msg_msg-16' already exists
[    2.404801] WARNING: CPU: 2 PID: 1 at mm/slab_common.c:107 __kmem_cache_create_args+0xb8/0x3b0
[    2.404842] Modules linked in:
[    2.404971] CPU: 2 UID: 0 PID: 1 Comm: swapper/0 Tainted: G        W          6.12.0-rc5mm-unstable-arm64+ torvalds#12
[    2.405026] Tainted: [W]=WARN
[    2.405043] Hardware name: QEMU QEMU Virtual Machine, BIOS 2024.02-2 03/11/2024
[    2.405057] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[    2.405079] pc : __kmem_cache_create_args+0xb8/0x3b0
[    2.405100] lr : __kmem_cache_create_args+0xb8/0x3b0
[    2.405111] sp : ffff800083d6fc50
[    2.405115] x29: ffff800083d6fc50 x28: fbff0000c1674410 x27: ffff8000820b0598
[    2.405135] x26: 000000000000ffd0 x25: 0000000000000010 x24: 0000000000006000
[    2.405153] x23: ffff800083d6fce8 x22: ffff8000832222e8 x21: ffff800083222388
[    2.405169] x20: fbff0000c1674410 x19: fdff0000c163d6c0 x18: ffff800083d80030
[    2.405185] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
[    2.405201] x14: 0000000000000000 x13: 0a73747369786520 x12: 79646165726c6120
[    2.405217] x11: 656820747563205b x10: 2d2d2d2d2d2d2d2d x9 : 0000000000000000
[    2.405233] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
[    2.405248] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000
[    2.405271] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
[    2.405287] Call trace:
[    2.405293]  __kmem_cache_create_args+0xb8/0x3b0
[    2.405305]  kmem_buckets_create+0xfc/0x320
[    2.405315]  init_msg_buckets+0x34/0x78
[    2.405326]  do_one_initcall+0x64/0x3c8
[    2.405337]  kernel_init_freeable+0x26c/0x578
[    2.405348]  kernel_init+0x3c/0x258
[    2.405360]  ret_from_fork+0x10/0x20
[    2.405370] ---[ end trace 0000000000000000 ]---

To address this, alias kmem_cache for sizes smaller than min alignment
to the aligned sized kmem_cache, as done with the default system kmalloc
bucket.

Fixes: b32801d ("mm/slab: Introduce kmem_buckets_create() and family")
Cc: <[email protected]> # v6.11+
Signed-off-by: Koichiro Den <[email protected]>
Reviewed-by: Catalin Marinas <[email protected]>
Tested-by: Catalin Marinas <[email protected]>
Signed-off-by: Vlastimil Babka <[email protected]>
mj22226 pushed a commit to mj22226/linux that referenced this pull request Nov 12, 2024
…buckets_create

commit 9c9201a upstream.

Commit b035f5a ("mm: slab: reduce the kmalloc() minimum alignment
if DMA bouncing possible") reduced ARCH_KMALLOC_MINALIGN to 8 on arm64.
However, with KASAN_HW_TAGS enabled, arch_slab_minalign() becomes 16.
This causes kmalloc_caches[*][8] to be aliased to kmalloc_caches[*][16],
resulting in kmem_buckets_create() attempting to create a kmem_cache for
size 16 twice. This duplication triggers warnings on boot:

[    2.325108] ------------[ cut here ]------------
[    2.325135] kmem_cache of name 'memdup_user-16' already exists
[    2.325783] WARNING: CPU: 0 PID: 1 at mm/slab_common.c:107 __kmem_cache_create_args+0xb8/0x3b0
[    2.327957] Modules linked in:
[    2.328550] CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.12.0-rc5mm-unstable-arm64+ torvalds#12
[    2.328683] Hardware name: QEMU QEMU Virtual Machine, BIOS 2024.02-2 03/11/2024
[    2.328790] pstate: 61000009 (nZCv daif -PAN -UAO -TCO +DIT -SSBS BTYPE=--)
[    2.328911] pc : __kmem_cache_create_args+0xb8/0x3b0
[    2.328930] lr : __kmem_cache_create_args+0xb8/0x3b0
[    2.328942] sp : ffff800083d6fc50
[    2.328961] x29: ffff800083d6fc50 x28: f2ff0000c1674410 x27: ffff8000820b0598
[    2.329061] x26: 000000007fffffff x25: 0000000000000010 x24: 0000000000002000
[    2.329101] x23: ffff800083d6fce8 x22: ffff8000832222e8 x21: ffff800083222388
[    2.329118] x20: f2ff0000c1674410 x19: f5ff0000c16364c0 x18: ffff800083d80030
[    2.329135] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
[    2.329152] x14: 0000000000000000 x13: 0a73747369786520 x12: 79646165726c6120
[    2.329169] x11: 656820747563205b x10: 2d2d2d2d2d2d2d2d x9 : 0000000000000000
[    2.329194] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
[    2.329210] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000
[    2.329226] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
[    2.329291] Call trace:
[    2.329407]  __kmem_cache_create_args+0xb8/0x3b0
[    2.329499]  kmem_buckets_create+0xfc/0x320
[    2.329526]  init_user_buckets+0x34/0x78
[    2.329540]  do_one_initcall+0x64/0x3c8
[    2.329550]  kernel_init_freeable+0x26c/0x578
[    2.329562]  kernel_init+0x3c/0x258
[    2.329574]  ret_from_fork+0x10/0x20
[    2.329698] ---[ end trace 0000000000000000 ]---

[    2.403704] ------------[ cut here ]------------
[    2.404716] kmem_cache of name 'msg_msg-16' already exists
[    2.404801] WARNING: CPU: 2 PID: 1 at mm/slab_common.c:107 __kmem_cache_create_args+0xb8/0x3b0
[    2.404842] Modules linked in:
[    2.404971] CPU: 2 UID: 0 PID: 1 Comm: swapper/0 Tainted: G        W          6.12.0-rc5mm-unstable-arm64+ torvalds#12
[    2.405026] Tainted: [W]=WARN
[    2.405043] Hardware name: QEMU QEMU Virtual Machine, BIOS 2024.02-2 03/11/2024
[    2.405057] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[    2.405079] pc : __kmem_cache_create_args+0xb8/0x3b0
[    2.405100] lr : __kmem_cache_create_args+0xb8/0x3b0
[    2.405111] sp : ffff800083d6fc50
[    2.405115] x29: ffff800083d6fc50 x28: fbff0000c1674410 x27: ffff8000820b0598
[    2.405135] x26: 000000000000ffd0 x25: 0000000000000010 x24: 0000000000006000
[    2.405153] x23: ffff800083d6fce8 x22: ffff8000832222e8 x21: ffff800083222388
[    2.405169] x20: fbff0000c1674410 x19: fdff0000c163d6c0 x18: ffff800083d80030
[    2.405185] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
[    2.405201] x14: 0000000000000000 x13: 0a73747369786520 x12: 79646165726c6120
[    2.405217] x11: 656820747563205b x10: 2d2d2d2d2d2d2d2d x9 : 0000000000000000
[    2.405233] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
[    2.405248] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000
[    2.405271] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
[    2.405287] Call trace:
[    2.405293]  __kmem_cache_create_args+0xb8/0x3b0
[    2.405305]  kmem_buckets_create+0xfc/0x320
[    2.405315]  init_msg_buckets+0x34/0x78
[    2.405326]  do_one_initcall+0x64/0x3c8
[    2.405337]  kernel_init_freeable+0x26c/0x578
[    2.405348]  kernel_init+0x3c/0x258
[    2.405360]  ret_from_fork+0x10/0x20
[    2.405370] ---[ end trace 0000000000000000 ]---

To address this, alias kmem_cache for sizes smaller than min alignment
to the aligned sized kmem_cache, as done with the default system kmalloc
bucket.

Fixes: b32801d ("mm/slab: Introduce kmem_buckets_create() and family")
Cc: <[email protected]> # v6.11+
Signed-off-by: Koichiro Den <[email protected]>
Reviewed-by: Catalin Marinas <[email protected]>
Tested-by: Catalin Marinas <[email protected]>
Signed-off-by: Vlastimil Babka <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
K900 pushed a commit to K900/linux that referenced this pull request Nov 14, 2024
…buckets_create

commit 9c9201a upstream.

Commit b035f5a ("mm: slab: reduce the kmalloc() minimum alignment
if DMA bouncing possible") reduced ARCH_KMALLOC_MINALIGN to 8 on arm64.
However, with KASAN_HW_TAGS enabled, arch_slab_minalign() becomes 16.
This causes kmalloc_caches[*][8] to be aliased to kmalloc_caches[*][16],
resulting in kmem_buckets_create() attempting to create a kmem_cache for
size 16 twice. This duplication triggers warnings on boot:

[    2.325108] ------------[ cut here ]------------
[    2.325135] kmem_cache of name 'memdup_user-16' already exists
[    2.325783] WARNING: CPU: 0 PID: 1 at mm/slab_common.c:107 __kmem_cache_create_args+0xb8/0x3b0
[    2.327957] Modules linked in:
[    2.328550] CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.12.0-rc5mm-unstable-arm64+ torvalds#12
[    2.328683] Hardware name: QEMU QEMU Virtual Machine, BIOS 2024.02-2 03/11/2024
[    2.328790] pstate: 61000009 (nZCv daif -PAN -UAO -TCO +DIT -SSBS BTYPE=--)
[    2.328911] pc : __kmem_cache_create_args+0xb8/0x3b0
[    2.328930] lr : __kmem_cache_create_args+0xb8/0x3b0
[    2.328942] sp : ffff800083d6fc50
[    2.328961] x29: ffff800083d6fc50 x28: f2ff0000c1674410 x27: ffff8000820b0598
[    2.329061] x26: 000000007fffffff x25: 0000000000000010 x24: 0000000000002000
[    2.329101] x23: ffff800083d6fce8 x22: ffff8000832222e8 x21: ffff800083222388
[    2.329118] x20: f2ff0000c1674410 x19: f5ff0000c16364c0 x18: ffff800083d80030
[    2.329135] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
[    2.329152] x14: 0000000000000000 x13: 0a73747369786520 x12: 79646165726c6120
[    2.329169] x11: 656820747563205b x10: 2d2d2d2d2d2d2d2d x9 : 0000000000000000
[    2.329194] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
[    2.329210] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000
[    2.329226] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
[    2.329291] Call trace:
[    2.329407]  __kmem_cache_create_args+0xb8/0x3b0
[    2.329499]  kmem_buckets_create+0xfc/0x320
[    2.329526]  init_user_buckets+0x34/0x78
[    2.329540]  do_one_initcall+0x64/0x3c8
[    2.329550]  kernel_init_freeable+0x26c/0x578
[    2.329562]  kernel_init+0x3c/0x258
[    2.329574]  ret_from_fork+0x10/0x20
[    2.329698] ---[ end trace 0000000000000000 ]---

[    2.403704] ------------[ cut here ]------------
[    2.404716] kmem_cache of name 'msg_msg-16' already exists
[    2.404801] WARNING: CPU: 2 PID: 1 at mm/slab_common.c:107 __kmem_cache_create_args+0xb8/0x3b0
[    2.404842] Modules linked in:
[    2.404971] CPU: 2 UID: 0 PID: 1 Comm: swapper/0 Tainted: G        W          6.12.0-rc5mm-unstable-arm64+ torvalds#12
[    2.405026] Tainted: [W]=WARN
[    2.405043] Hardware name: QEMU QEMU Virtual Machine, BIOS 2024.02-2 03/11/2024
[    2.405057] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[    2.405079] pc : __kmem_cache_create_args+0xb8/0x3b0
[    2.405100] lr : __kmem_cache_create_args+0xb8/0x3b0
[    2.405111] sp : ffff800083d6fc50
[    2.405115] x29: ffff800083d6fc50 x28: fbff0000c1674410 x27: ffff8000820b0598
[    2.405135] x26: 000000000000ffd0 x25: 0000000000000010 x24: 0000000000006000
[    2.405153] x23: ffff800083d6fce8 x22: ffff8000832222e8 x21: ffff800083222388
[    2.405169] x20: fbff0000c1674410 x19: fdff0000c163d6c0 x18: ffff800083d80030
[    2.405185] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
[    2.405201] x14: 0000000000000000 x13: 0a73747369786520 x12: 79646165726c6120
[    2.405217] x11: 656820747563205b x10: 2d2d2d2d2d2d2d2d x9 : 0000000000000000
[    2.405233] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
[    2.405248] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000
[    2.405271] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
[    2.405287] Call trace:
[    2.405293]  __kmem_cache_create_args+0xb8/0x3b0
[    2.405305]  kmem_buckets_create+0xfc/0x320
[    2.405315]  init_msg_buckets+0x34/0x78
[    2.405326]  do_one_initcall+0x64/0x3c8
[    2.405337]  kernel_init_freeable+0x26c/0x578
[    2.405348]  kernel_init+0x3c/0x258
[    2.405360]  ret_from_fork+0x10/0x20
[    2.405370] ---[ end trace 0000000000000000 ]---

To address this, alias kmem_cache for sizes smaller than min alignment
to the aligned sized kmem_cache, as done with the default system kmalloc
bucket.

Fixes: b32801d ("mm/slab: Introduce kmem_buckets_create() and family")
Cc: <[email protected]> # v6.11+
Signed-off-by: Koichiro Den <[email protected]>
Reviewed-by: Catalin Marinas <[email protected]>
Tested-by: Catalin Marinas <[email protected]>
Signed-off-by: Vlastimil Babka <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
intel-lab-lkp pushed a commit to intel-lab-lkp/linux that referenced this pull request Nov 21, 2024
commit cf96b8e upstream.

ASan reports a memory leak caused by evlist not being deleted on exit in
perf-report, perf-script and perf-data.
The problem is caused by evlist->session not being deleted, which is
allocated in perf_session__read_header, called in perf_session__new if
perf_data is in read mode.
In case of write mode, the session->evlist is filled by the caller.
This patch solves the problem by calling evlist__delete in
perf_session__delete if perf_data is in read mode.

Changes in v2:
 - call evlist__delete from within perf_session__delete

v1: https://lore.kernel.org/lkml/[email protected]/

ASan report follows:

$ ./perf script report flamegraph
=================================================================
==227640==ERROR: LeakSanitizer: detected memory leaks

<SNIP unrelated>

Indirect leak of 2704 byte(s) in 1 object(s) allocated from:
    #0 0x4f4137 in calloc (/home/user/linux/tools/perf/perf+0x4f4137)
    #1 0xbe3d56 in zalloc /home/user/linux/tools/lib/perf/../../lib/zalloc.c:8:9
    #2 0x7f999e in evlist__new /home/user/linux/tools/perf/util/evlist.c:77:26
    #3 0x8ad938 in perf_session__read_header /home/user/linux/tools/perf/util/header.c:3797:20
    #4 0x8ec714 in perf_session__open /home/user/linux/tools/perf/util/session.c:109:6
    #5 0x8ebe83 in perf_session__new /home/user/linux/tools/perf/util/session.c:213:10
    torvalds#6 0x60c6de in cmd_script /home/user/linux/tools/perf/builtin-script.c:3856:12
    torvalds#7 0x7b2930 in run_builtin /home/user/linux/tools/perf/perf.c:313:11
    torvalds#8 0x7b120f in handle_internal_command /home/user/linux/tools/perf/perf.c:365:8
    torvalds#9 0x7b2493 in run_argv /home/user/linux/tools/perf/perf.c:409:2
    torvalds#10 0x7b0c89 in main /home/user/linux/tools/perf/perf.c:539:3
    torvalds#11 0x7f5260654b74  (/lib64/libc.so.6+0x27b74)

Indirect leak of 568 byte(s) in 1 object(s) allocated from:
    #0 0x4f4137 in calloc (/home/user/linux/tools/perf/perf+0x4f4137)
    #1 0xbe3d56 in zalloc /home/user/linux/tools/lib/perf/../../lib/zalloc.c:8:9
    #2 0x80ce88 in evsel__new_idx /home/user/linux/tools/perf/util/evsel.c:268:24
    #3 0x8aed93 in evsel__new /home/user/linux/tools/perf/util/evsel.h:210:9
    #4 0x8ae07e in perf_session__read_header /home/user/linux/tools/perf/util/header.c:3853:11
    #5 0x8ec714 in perf_session__open /home/user/linux/tools/perf/util/session.c:109:6
    torvalds#6 0x8ebe83 in perf_session__new /home/user/linux/tools/perf/util/session.c:213:10
    torvalds#7 0x60c6de in cmd_script /home/user/linux/tools/perf/builtin-script.c:3856:12
    torvalds#8 0x7b2930 in run_builtin /home/user/linux/tools/perf/perf.c:313:11
    torvalds#9 0x7b120f in handle_internal_command /home/user/linux/tools/perf/perf.c:365:8
    torvalds#10 0x7b2493 in run_argv /home/user/linux/tools/perf/perf.c:409:2
    torvalds#11 0x7b0c89 in main /home/user/linux/tools/perf/perf.c:539:3
    torvalds#12 0x7f5260654b74  (/lib64/libc.so.6+0x27b74)

Indirect leak of 264 byte(s) in 1 object(s) allocated from:
    #0 0x4f4137 in calloc (/home/user/linux/tools/perf/perf+0x4f4137)
    #1 0xbe3d56 in zalloc /home/user/linux/tools/lib/perf/../../lib/zalloc.c:8:9
    #2 0xbe3e70 in xyarray__new /home/user/linux/tools/lib/perf/xyarray.c:10:23
    #3 0xbd7754 in perf_evsel__alloc_id /home/user/linux/tools/lib/perf/evsel.c:361:21
    #4 0x8ae201 in perf_session__read_header /home/user/linux/tools/perf/util/header.c:3871:7
    #5 0x8ec714 in perf_session__open /home/user/linux/tools/perf/util/session.c:109:6
    torvalds#6 0x8ebe83 in perf_session__new /home/user/linux/tools/perf/util/session.c:213:10
    torvalds#7 0x60c6de in cmd_script /home/user/linux/tools/perf/builtin-script.c:3856:12
    torvalds#8 0x7b2930 in run_builtin /home/user/linux/tools/perf/perf.c:313:11
    torvalds#9 0x7b120f in handle_internal_command /home/user/linux/tools/perf/perf.c:365:8
    torvalds#10 0x7b2493 in run_argv /home/user/linux/tools/perf/perf.c:409:2
    torvalds#11 0x7b0c89 in main /home/user/linux/tools/perf/perf.c:539:3
    torvalds#12 0x7f5260654b74  (/lib64/libc.so.6+0x27b74)

Indirect leak of 32 byte(s) in 1 object(s) allocated from:
    #0 0x4f4137 in calloc (/home/user/linux/tools/perf/perf+0x4f4137)
    #1 0xbe3d56 in zalloc /home/user/linux/tools/lib/perf/../../lib/zalloc.c:8:9
    #2 0xbd77e0 in perf_evsel__alloc_id /home/user/linux/tools/lib/perf/evsel.c:365:14
    #3 0x8ae201 in perf_session__read_header /home/user/linux/tools/perf/util/header.c:3871:7
    #4 0x8ec714 in perf_session__open /home/user/linux/tools/perf/util/session.c:109:6
    #5 0x8ebe83 in perf_session__new /home/user/linux/tools/perf/util/session.c:213:10
    torvalds#6 0x60c6de in cmd_script /home/user/linux/tools/perf/builtin-script.c:3856:12
    torvalds#7 0x7b2930 in run_builtin /home/user/linux/tools/perf/perf.c:313:11
    torvalds#8 0x7b120f in handle_internal_command /home/user/linux/tools/perf/perf.c:365:8
    torvalds#9 0x7b2493 in run_argv /home/user/linux/tools/perf/perf.c:409:2
    torvalds#10 0x7b0c89 in main /home/user/linux/tools/perf/perf.c:539:3
    torvalds#11 0x7f5260654b74  (/lib64/libc.so.6+0x27b74)

Indirect leak of 7 byte(s) in 1 object(s) allocated from:
    #0 0x4b8207 in strdup (/home/user/linux/tools/perf/perf+0x4b8207)
    #1 0x8b4459 in evlist__set_event_name /home/user/linux/tools/perf/util/header.c:2292:16
    #2 0x89d862 in process_event_desc /home/user/linux/tools/perf/util/header.c:2313:3
    #3 0x8af319 in perf_file_section__process /home/user/linux/tools/perf/util/header.c:3651:9
    #4 0x8aa6e9 in perf_header__process_sections /home/user/linux/tools/perf/util/header.c:3427:9
    #5 0x8ae3e7 in perf_session__read_header /home/user/linux/tools/perf/util/header.c:3886:2
    torvalds#6 0x8ec714 in perf_session__open /home/user/linux/tools/perf/util/session.c:109:6
    torvalds#7 0x8ebe83 in perf_session__new /home/user/linux/tools/perf/util/session.c:213:10
    torvalds#8 0x60c6de in cmd_script /home/user/linux/tools/perf/builtin-script.c:3856:12
    torvalds#9 0x7b2930 in run_builtin /home/user/linux/tools/perf/perf.c:313:11
    torvalds#10 0x7b120f in handle_internal_command /home/user/linux/tools/perf/perf.c:365:8
    torvalds#11 0x7b2493 in run_argv /home/user/linux/tools/perf/perf.c:409:2
    torvalds#12 0x7b0c89 in main /home/user/linux/tools/perf/perf.c:539:3
    torvalds#13 0x7f5260654b74  (/lib64/libc.so.6+0x27b74)

SUMMARY: AddressSanitizer: 3728 byte(s) leaked in 7 allocation(s).

Signed-off-by: Riccardo Mancini <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Cc: [email protected] # 5.10.228
Signed-off-by: Shuai Xue <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
l1k added a commit to l1k/linux that referenced this pull request Nov 28, 2024
Dennis reports a boot crash on recent Lenovo laptops with a USB4 dock.

Since commit 0fc7088 ("thunderbolt: Reset USB4 v2 host router") and
commit 59a54c5 ("thunderbolt: Reset topology created by the boot
firmware"), USB4 v2 and v1 Host Routers are reset on probe of the
thunderbolt driver.

The reset clears the Presence Detect State and Data Link Layer Link Active
bits at the USB4 Host Router's Root Port and thus causes hot removal of
the dock.

The crash occurs when pciehp is unbound from one of the dock's Downstream
Ports:  pciehp creates a pci_slot on bind and destroys it on unbind.  The
pci_slot contains a pointer to the pci_bus below the Downstream Port, but
a reference on that pci_bus is never acquired.  The pci_bus is destroyed
before the pci_slot, so a use-after-free ensues when pci_slot_release()
accesses slot->bus.

In principle this should not happen because pci_stop_bus_device() unbinds
pciehp (and therefore destroys the pci_slot) before the pci_bus is
destroyed by pci_remove_bus_device().

However the stacktrace provided by Dennis shows that pciehp is unbound
from pci_remove_bus_device() instead of pci_stop_bus_device().
To understand the significance of this, one needs to know that the PCI
core uses a two step process to remove a portion of the hierarchy:  It
first unbinds all drivers in the sub-hierarchy in pci_stop_bus_device()
and then actually removes the devices in pci_remove_bus_device().
There is no precaution to prevent driver binding in-between
pci_stop_bus_device() and pci_remove_bus_device().

In Dennis' case, it seems removal of the hierarchy by pciehp races with
driver binding by pci_bus_add_devices().  pciehp is bound to the
Downstream Port after pci_stop_bus_device() has run, so it is unbound by
pci_remove_bus_device() instead of pci_stop_bus_device().  Because the
pci_bus has already been destroyed at that point, accesses to it result in
a use-after-free.

One might conclude that driver binding needs to be prevented after
pci_stop_bus_device() has run.  However it seems risky that pci_slot
points to pci_bus without holding a reference.  Solely relying on correct
ordering of driver unbind versus pci_bus destruction is certainly not
defensive programming.

If pci_slot has a need to access data in pci_bus, it ought to acquire a
reference.  Amend pci_create_slot() accordingly.  Dennis reports that the
crash is not reproducible with this change.

Abridged stacktrace:

  pcieport 0000:00:07.0: PME: Signaling with IRQ 156
  pcieport 0000:00:07.0: pciehp: Slot torvalds#12 AttnBtn- PwrCtrl- MRL- AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis- LLActRep+
  pci_bus 0000:20: dev 00, created physical slot 12
  pcieport 0000:00:07.0: pciehp: Slot(12): Card not present
  ...
  pcieport 0000:21:02.0: pciehp: pcie_disable_notification: SLOTCTRL d8 write cmd 0
  Oops: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b6b: 0000 [#1] PREEMPT SMP NOPTI
  CPU: 13 UID: 0 PID: 134 Comm: irq/156-pciehp Not tainted 6.11.0-devel+ #1
  RIP: 0010:dev_driver_string+0x12/0x40
  pci_destroy_slot
  pciehp_remove
  pcie_port_remove_service
  device_release_driver_internal
  bus_remove_device
  device_del
  device_unregister
  remove_iter
  device_for_each_child
  pcie_portdrv_remove
  pci_device_remove
  device_release_driver_internal
  bus_remove_device
  device_del
  pci_remove_bus_device (recursive invocation)
  pci_remove_bus_device
  pciehp_unconfigure_device
  pciehp_disable_slot
  pciehp_handle_presence_or_link_change
  pciehp_ist

Reported-by: Dennis Wassenberg <[email protected]>
Tested-by: Dennis Wassenberg <[email protected]>
Closes: https://lore.kernel.org/r/[email protected]/
Signed-off-by: Lukas Wunner <[email protected]>
Reviewed-by: Mika Westerberg <[email protected]>
Cc: [email protected]

I am tempted to remove the call to device_release_driver() from
pci_stop_dev() and just rely on driver unbinding by device_del().
It would simplify and rationalize the code.  The call was introduced by
commit c4a0a5d (PCI: Move device_del() from pci_stop_dev() to
pci_destroy_dev()) without providing an explicit reason.

Dennis stress-tested driver unbinding via device_del() without witnessing
any problems.  The only downside I see is that it would re-introduce the
cosmetic issue avoided by commit 16b6c8b ("PCI: Detach driver before
procfs & sysfs teardown on device remove").

Preventing driver binding after pci_stop_bus_device() should be achieved
by this one-line patch, though that's still racy as pci_bus_add_devices()
might revert the match_driver flag to true after pci_stop_bus_device() has
set it to false:
https://lore.kernel.org/r/[email protected]/

An alternative would be to serialize removal of the hierarchy with
pci_bus_add_devices() by way of pci_lock_rescan_remove():
https://lore.kernel.org/r/[email protected]/

Both approaches are yet to be tested by Dennis.  Personally I would like
to avoid the pci_lock_rescan_remove() approach.  We should try to move
away from this big lock and use finer grained locking instead.  So again,
just dropping the call to device_release_driver() would be the simplest
and most preferred approach from my point of view.  Thoughts?
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