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Btrfs device related enhancements #3

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Btrfs device related enhancements #3

wants to merge 29 commits into from

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asj
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@asj asj commented Oct 7, 2015

Please consider these fixes, in the area of handling devices and sysfs. Mainly they are bug fixes and framework changes. And towards the end of this patch set, I have two patches which are introducing two new features, device delete by devid and sysfs attributes for btrfs pool. These patches were sent to mailing list before.
Kindly note few of the subject are changed for good and to backtrack the old subject are maintained in the changelog. Also the review comment changes that some of the patches went through are also in the changelog, which probably should be deleted when merged.

Thanks, Anand

asj and others added 29 commits September 29, 2015 16:29
Signed-off-by: Anand Jain <[email protected]>
Signed-off-by: David Sterba <[email protected]>
This will return EIO when __bread() fails to read SB,
instead of EINVAL.

Signed-off-by: Anand Jain <[email protected]>
Signed-off-by: David Sterba <[email protected]>
…INTK defined

error handling logic behaves differently with or without
CONFIG_PRINTK defined, since there are two copies of the same
function which a bit of different logic

One, when CONFIG_PRINTK is defined, code is

__btrfs_std_error(..)
{
::
       save_error_info(fs_info);
       if (sb->s_flags & MS_BORN)
               btrfs_handle_error(fs_info);
}

and two when CONFIG_PRINTK is not defined, the code is

__btrfs_std_error(..)
{
::
       if (sb->s_flags & MS_BORN) {
               save_error_info(fs_info);
               btrfs_handle_error(fs_info);
        }
}

I doubt if this was intentional ? and appear to have caused since
we maintain two copies of the same function and they got diverged
with commits.

Now to decide which logic is correct reviewed changes as below,

 533574c
Commit added two copies of this function

 cf79ffb
Commit made change to only one copy of the function and to the
copy when CONFIG_PRINTK is defined.

To fix this, instead of maintaining two copies of same function
approach, maintain single function, and just put the extra
portion of the code under CONFIG_PRINTK define.

This patch just does that. And keeps code of with CONFIG_PRINTK
defined.

Signed-off-by: Anand Jain <[email protected]>
Signed-off-by: David Sterba <[email protected]>
btrfs_error() and btrfs_std_error() does the same thing
and calls _btrfs_std_error(), so consolidate them together.
And the main motivation is that btrfs_error() is closely
named with btrfs_err(), one handles error action the other
is to log the error, so don't closely name them.

Signed-off-by: Anand Jain <[email protected]>
Suggested-by: David Sterba <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>
…ot found

Use btrfs specific error code BTRFS_ERROR_DEV_MISSING_NOT_FOUND instead
of -ENOENT.  Next this removes the logging when user specifies "missing"
and we don't find it in the kernel device list. Logging are for system
events not for user input errors.

Signed-off-by: Anand Jain <[email protected]>
Signed-off-by: David Sterba <[email protected]>
This uses a chunk of code from btrfs_read_dev_super() and creates
a function called btrfs_read_dev_one_super() so that next patch
can use it for scratch superblock.

Signed-off-by: Anand Jain <[email protected]>
[renamed bufhead to bh]
Signed-off-by: David Sterba <[email protected]>
This patch updates and renames btrfs_scratch_superblocks, (which is used
by the replace device thread), with those fixes from the scratch
superblock code section of btrfs_rm_device(). The fixes are:
  Scratch all copies of superblock
  Notify kobject that superblock has been changed
  Update time on the device

So that btrfs_rm_device() can use the function
btrfs_scratch_superblocks() instead of its own scratch code. And further
replace deivce code which similarly releases device back to the system,
will have the fixes from the btrfs device delete.

Signed-off-by: Anand Jain <[email protected]>
[renamed to btrfs_scratch_superblock]
Signed-off-by: David Sterba <[email protected]>
By general rule of thumb there shouldn't be any way that user land
could trigger a kernel operation just by sending wrong arguments.

Here do commit cleanups after user input has been verified.

Signed-off-by: Anand Jain <[email protected]>
Signed-off-by: David Sterba <[email protected]>
Originally the message was not in a helper but ended up there. We should
print error messages from callers instead.

Signed-off-by: Anand Jain <[email protected]>
[reworded subject and changelog]
Signed-off-by: David Sterba <[email protected]>
Signed-off-by: Anand Jain <[email protected]>
[reworded subject and changelog]
Signed-off-by: David Sterba <[email protected]>
To avoid deadlock described in commit 084b6e7 ("btrfs: Fix a
lockdep warning when running xfstest."), we should move kobj stuff out
of dev_replace lock range.

  "It is because the btrfs_kobj_{add/rm}_device() will call memory
  allocation with GFP_KERNEL,
  which may flush fs page cache to free space, waiting for it self to do
  the commit, causing the deadlock.

  To solve the problem, move btrfs_kobj_{add/rm}_device() out of the
  dev_replace lock range, also involing split the
  btrfs_rm_dev_replace_srcdev() function into remove and free parts.

  Now only btrfs_rm_dev_replace_remove_srcdev() is called in dev_replace
  lock range, and kobj_{add/rm} and btrfs_rm_dev_replace_free_srcdev() are
  called out of the lock range."

Signed-off-by: Liu Bo <[email protected]>
Signed-off-by: Anand Jain <[email protected]>
[added lockup description]
Signed-off-by: David Sterba <[email protected]>
This patch will log return value of add/del_qgroup_relation()
and pass the err code of btrfs_run_qgroups to the btrfs_std_error().

Signed-off-by: Anand Jain <[email protected]>
A part of code from btrfs_scan_one_device() is moved to a new
function btrfs_read_disk_super(), so that former function looks
cleaner and moves the code to ensure null terminating label to it as well.
Further there is opportunity to merge various duplicate
code on read disk super. Earlier attempt on this was highlighted
that there was some issues for which there are multiple versions,
however it was not clear what was issue. So until its worked out
we can keep it in a separate function.

Signed-off-by: Anand Jain <[email protected]>
Optional Label may or may not be set, or it might be set at
some time later. However while debugging to search
through the kernel logs the scripts would need the logs to
be consistent, so logs search key words shouldn't depend on the
optional variables, instead fsid is better.

Signed-off-by: Anand Jain <[email protected]>
From the issue diagnosable point of view, log if the device path is
changed.

Signed-off-by: Anand Jain <[email protected]>
Looks like oversight, call brelse() when checksum fails. Further down the
code, in the non error path, we do call brelse() and so we don't see
brelse() in the goto error paths.

Signed-off-by: Anand Jain <[email protected]>
This adds an enhancement to show the seed fsid and its devices
on the btrfs sysfs.

The way sprouting handles fs_devices:
      clone seed fs_devices and add to the fs_uuids
      mem copy seed fs_devices and assign to fs_devices->seed (move dev_list)
      evacuate seed fs_devices contents to hold sprout fs devices contents

  So to be inline with this fs_devices changes during seeding,
  represent seed fsid under the sprout fsid, this is achieved
  by using the kobject_move()
  The end result will be,
    /sys/fs/btrfs/sprout-fsid/seed/level-1-seed-fsid/seed/(if)level-2-seed-fsid

Signed-off-by: Anand Jain <[email protected]>
We need fsid kobject to hold pool attributes however
its created only when fs is mounted. So, this patch
changes the life cycle of the fsid and devices kobjects
/sys/fs/btrfs/<fsid> and /sys/fs/btrfs/<fsid>/devices,
from created and destroyed by mount and unmount event
to created and destroyed by scanned and module-unload
events respectively.

However this does not alter life cycle of fs attributes as such.

Signed-off-by: Anand Jain <[email protected]>
move a section of btrfs_rm_device() code to check for min number
of the devices into the function __check_raid_min_devices()

v2: commit update and title renamed from
    Btrfs: move check for min number of devices to a function

Signed-off-by: Anand Jain <[email protected]>
__check_raid_min_device() which was pealed from btrfs_rm_device()
maintianed its original code to show the block move. This patch
cleans up __check_raid_min_device().

Signed-off-by: Anand Jain <[email protected]>
The patch renames btrfs_dev_replace_find_srcdev() to
btrfs_find_device_by_user_input() and moves it to volumes.c.
so that delete device can use it.

v2: changed title from
    'Btrfs: create rename btrfs_dev_replace_find_srcdev()'
    and commit update

Signed-off-by: Anand Jain <[email protected]>
btrfs_rm_device() has a section of the code which can be replaced
btrfs_find_device_by_user_input()

Signed-off-by: Anand Jain <[email protected]>
The operation of device replace and device delete follows same steps
upto some depth with in btrfs kernel, however they don't share codes.
This enhancement will help replace and delete to share codes.

Btrfs: enhance check device_path in btrfs_find_device_by_user_input()

Signed-off-by: Anand Jain <[email protected]>
With the previous patches now the btrfs_scratch_superblocks()
is ready to be used in btrfs_rm_device() so use it.

Signed-off-by: Anand Jain <[email protected]>
This patch makes btrfs_fs_devices and btrfs_device information readable
from sysfs. This uses the sysfs group visible entry point to mark certain
attributes visible/hidden depending the FS state.

The new extended layout is as shown below.

/sys/fs/btrfs/
	./7b047f4d-c2ce-4f22-94a3-68c09057f1bf*
		fsid*
		missing_devices
		num_devices*
		open_devices
		opened*
		rotating
		rw_devices
		seeding
		total_devices*
		total_rw_bytes
		./e6701882-220a-4416-98ac-a99f095bddcc*
			active_pending
			bdev
			bytes_used
			can_discard
			devid*
			dev_root_fsid
			devstats_valid
			dev_totalbytes
			generation*
			in_fs_metadata
			io_align
			io_width
			missing
			name*
			nobarriers
			replace_tgtdev
			sector_size
			total_bytes
			type
			uuid*
			writeable

(* indicates that attribute will be visible even when device is
unmounted but registered with btrfs kernel)

v2: use btrfs_error() not btrfs_err()
reword subject form :
    Btrfs: add sysfs layout to show btrfs_fs_devices and btrfs_device attributes

Signed-off-by: Anand Jain <[email protected]>
@asj asj closed this Oct 8, 2015
kdave pushed a commit that referenced this pull request Jul 17, 2024
Petr Machata says:

====================
selftest: Clean-up and stabilize mirroring tests

The mirroring selftests work by sending ICMP traffic between two hosts.
Along the way, this traffic is mirrored to a gretap netdevice, and counter
taps are then installed strategically along the path of the mirrored
traffic to verify the mirroring took place.

The problem with this is that besides mirroring the primary traffic, any
other service traffic is mirrored as well. At the same time, because the
tests need to work in HW-offloaded scenarios, the ability of the device to
do arbitrary packet inspection should not be taken for granted. Most tests
therefore simply use matchall, one uses flower to match on IP address.
As a result, the selftests are noisy.

mirror_test() accommodated this noisiness by giving the counters an
allowance of several packets. But that only works up to a point, and on
busy systems won't be always enough.

In this patch set, clean up and stabilize the mirroring selftests. The
original intention was to port the tests over to UDP, but the logic of
ICMP ends up being so entangled in the mirroring selftests that the
changes feel overly invasive. Instead, ICMP is kept, but where possible,
we match on ICMP message type, thus filtering out hits by other ICMP
messages.

Where this is not practical (where the counter tap is put on a device
that carries encapsulated packets), switch the counter condition to _at
least_ X observed packets. This is less robust, but barely so --
probably the only scenario that this would not catch is something like
erroneous packet duplication, which would hopefully get caught by the
numerous other tests in this extensive suite.

- Patches #1 to #3 clean up parameters at various helpers.

- Patches #4 to #6 stabilize the mirroring selftests as described above.

- Mirroring tests currently allow testing SW datapath even on HW
  netdevices by trapping traffic to the SW datapath. This complicates
  the tests a bit without a good reason: to test SW datapath, just run
  the selftests on the veth topology. Thus in patch #7, drop support for
  this dual SW/HW testing.

- At this point, some cleanups were either made possible by the previous
  patches, or were always possible. In patches #8 to torvalds#11, realize these
  cleanups.

- In patch torvalds#12, fix mlxsw mirror_gre selftest to respect setting TESTS.
====================

Signed-off-by: David S. Miller <[email protected]>
kdave pushed a commit that referenced this pull request Jul 17, 2024
Sebastian Andrzej Siewior says:

====================
net: bpf_net_context cleanups.

a small series with bpf_net_context cleanups/ improvements.
Jakub asked for #1 and #2 and while looking around I made #3.
====================

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Paolo Abeni <[email protected]>
kdave pushed a commit that referenced this pull request Jul 17, 2024
…_child().

syzkaller reported KMSAN splat in tcp_create_openreq_child(). [0]

The uninit variable is tcp_rsk(req)->ao_keyid.

tcp_rsk(req)->ao_keyid is initialised only when tcp_conn_request() finds
a valid TCP AO option in SYN.  Then, tcp_rsk(req)->used_tcp_ao is set
accordingly.

Let's not read tcp_rsk(req)->ao_keyid when tcp_rsk(req)->used_tcp_ao is
false.

[0]:
BUG: KMSAN: uninit-value in tcp_create_openreq_child+0x198b/0x1ff0 net/ipv4/tcp_minisocks.c:610
 tcp_create_openreq_child+0x198b/0x1ff0 net/ipv4/tcp_minisocks.c:610
 tcp_v4_syn_recv_sock+0x18e/0x2170 net/ipv4/tcp_ipv4.c:1754
 tcp_check_req+0x1a3e/0x20c0 net/ipv4/tcp_minisocks.c:852
 tcp_v4_rcv+0x26a4/0x53a0 net/ipv4/tcp_ipv4.c:2265
 ip_protocol_deliver_rcu+0x884/0x1270 net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x30f/0x530 net/ipv4/ip_input.c:233
 NF_HOOK include/linux/netfilter.h:314 [inline]
 ip_local_deliver+0x230/0x4c0 net/ipv4/ip_input.c:254
 dst_input include/net/dst.h:460 [inline]
 ip_sublist_rcv_finish net/ipv4/ip_input.c:580 [inline]
 ip_list_rcv_finish net/ipv4/ip_input.c:631 [inline]
 ip_sublist_rcv+0x10f7/0x13e0 net/ipv4/ip_input.c:639
 ip_list_rcv+0x952/0x9c0 net/ipv4/ip_input.c:674
 __netif_receive_skb_list_ptype net/core/dev.c:5703 [inline]
 __netif_receive_skb_list_core+0xd92/0x11d0 net/core/dev.c:5751
 __netif_receive_skb_list net/core/dev.c:5803 [inline]
 netif_receive_skb_list_internal+0xd8f/0x1350 net/core/dev.c:5895
 gro_normal_list include/net/gro.h:515 [inline]
 napi_complete_done+0x3f2/0x990 net/core/dev.c:6246
 e1000_clean+0x1fa4/0x5e50 drivers/net/ethernet/intel/e1000/e1000_main.c:3808
 __napi_poll+0xd9/0x990 net/core/dev.c:6771
 napi_poll net/core/dev.c:6840 [inline]
 net_rx_action+0x90f/0x17e0 net/core/dev.c:6962
 handle_softirqs+0x152/0x6b0 kernel/softirq.c:554
 __do_softirq kernel/softirq.c:588 [inline]
 invoke_softirq kernel/softirq.c:428 [inline]
 __irq_exit_rcu kernel/softirq.c:637 [inline]
 irq_exit_rcu+0x5d/0x120 kernel/softirq.c:649
 common_interrupt+0x83/0x90 arch/x86/kernel/irq.c:278
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693
 __msan_instrument_asm_store+0xd6/0xe0
 arch_atomic_inc arch/x86/include/asm/atomic.h:53 [inline]
 raw_atomic_inc include/linux/atomic/atomic-arch-fallback.h:992 [inline]
 atomic_inc include/linux/atomic/atomic-instrumented.h:436 [inline]
 page_ref_inc include/linux/page_ref.h:153 [inline]
 folio_ref_inc include/linux/page_ref.h:160 [inline]
 filemap_map_order0_folio mm/filemap.c:3596 [inline]
 filemap_map_pages+0x11c7/0x2270 mm/filemap.c:3644
 do_fault_around mm/memory.c:4879 [inline]
 do_read_fault mm/memory.c:4912 [inline]
 do_fault mm/memory.c:5051 [inline]
 do_pte_missing mm/memory.c:3897 [inline]
 handle_pte_fault mm/memory.c:5381 [inline]
 __handle_mm_fault mm/memory.c:5524 [inline]
 handle_mm_fault+0x3677/0x6f00 mm/memory.c:5689
 do_user_addr_fault+0x1373/0x2b20 arch/x86/mm/fault.c:1338
 handle_page_fault arch/x86/mm/fault.c:1481 [inline]
 exc_page_fault+0x54/0xc0 arch/x86/mm/fault.c:1539
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

Uninit was stored to memory at:
 tcp_create_openreq_child+0x1984/0x1ff0 net/ipv4/tcp_minisocks.c:611
 tcp_v4_syn_recv_sock+0x18e/0x2170 net/ipv4/tcp_ipv4.c:1754
 tcp_check_req+0x1a3e/0x20c0 net/ipv4/tcp_minisocks.c:852
 tcp_v4_rcv+0x26a4/0x53a0 net/ipv4/tcp_ipv4.c:2265
 ip_protocol_deliver_rcu+0x884/0x1270 net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x30f/0x530 net/ipv4/ip_input.c:233
 NF_HOOK include/linux/netfilter.h:314 [inline]
 ip_local_deliver+0x230/0x4c0 net/ipv4/ip_input.c:254
 dst_input include/net/dst.h:460 [inline]
 ip_sublist_rcv_finish net/ipv4/ip_input.c:580 [inline]
 ip_list_rcv_finish net/ipv4/ip_input.c:631 [inline]
 ip_sublist_rcv+0x10f7/0x13e0 net/ipv4/ip_input.c:639
 ip_list_rcv+0x952/0x9c0 net/ipv4/ip_input.c:674
 __netif_receive_skb_list_ptype net/core/dev.c:5703 [inline]
 __netif_receive_skb_list_core+0xd92/0x11d0 net/core/dev.c:5751
 __netif_receive_skb_list net/core/dev.c:5803 [inline]
 netif_receive_skb_list_internal+0xd8f/0x1350 net/core/dev.c:5895
 gro_normal_list include/net/gro.h:515 [inline]
 napi_complete_done+0x3f2/0x990 net/core/dev.c:6246
 e1000_clean+0x1fa4/0x5e50 drivers/net/ethernet/intel/e1000/e1000_main.c:3808
 __napi_poll+0xd9/0x990 net/core/dev.c:6771
 napi_poll net/core/dev.c:6840 [inline]
 net_rx_action+0x90f/0x17e0 net/core/dev.c:6962
 handle_softirqs+0x152/0x6b0 kernel/softirq.c:554
 __do_softirq kernel/softirq.c:588 [inline]
 invoke_softirq kernel/softirq.c:428 [inline]
 __irq_exit_rcu kernel/softirq.c:637 [inline]
 irq_exit_rcu+0x5d/0x120 kernel/softirq.c:649
 common_interrupt+0x83/0x90 arch/x86/kernel/irq.c:278
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693

Uninit was created at:
 __alloc_pages_noprof+0x82d/0xcb0 mm/page_alloc.c:4706
 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:296 [inline]
 alloc_slab_page mm/slub.c:2265 [inline]
 allocate_slab mm/slub.c:2428 [inline]
 new_slab+0x2af/0x14e0 mm/slub.c:2481
 ___slab_alloc+0xf73/0x3150 mm/slub.c:3667
 __slab_alloc mm/slub.c:3757 [inline]
 __slab_alloc_node mm/slub.c:3810 [inline]
 slab_alloc_node mm/slub.c:3990 [inline]
 kmem_cache_alloc_noprof+0x53a/0x9f0 mm/slub.c:4009
 reqsk_alloc_noprof net/ipv4/inet_connection_sock.c:920 [inline]
 inet_reqsk_alloc+0x63/0x700 net/ipv4/inet_connection_sock.c:951
 tcp_conn_request+0x339/0x4860 net/ipv4/tcp_input.c:7177
 tcp_v4_conn_request+0x13b/0x190 net/ipv4/tcp_ipv4.c:1719
 tcp_rcv_state_process+0x2dd/0x4a10 net/ipv4/tcp_input.c:6711
 tcp_v4_do_rcv+0xbee/0x10d0 net/ipv4/tcp_ipv4.c:1932
 tcp_v4_rcv+0x3fad/0x53a0 net/ipv4/tcp_ipv4.c:2334
 ip_protocol_deliver_rcu+0x884/0x1270 net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x30f/0x530 net/ipv4/ip_input.c:233
 NF_HOOK include/linux/netfilter.h:314 [inline]
 ip_local_deliver+0x230/0x4c0 net/ipv4/ip_input.c:254
 dst_input include/net/dst.h:460 [inline]
 ip_sublist_rcv_finish net/ipv4/ip_input.c:580 [inline]
 ip_list_rcv_finish net/ipv4/ip_input.c:631 [inline]
 ip_sublist_rcv+0x10f7/0x13e0 net/ipv4/ip_input.c:639
 ip_list_rcv+0x952/0x9c0 net/ipv4/ip_input.c:674
 __netif_receive_skb_list_ptype net/core/dev.c:5703 [inline]
 __netif_receive_skb_list_core+0xd92/0x11d0 net/core/dev.c:5751
 __netif_receive_skb_list net/core/dev.c:5803 [inline]
 netif_receive_skb_list_internal+0xd8f/0x1350 net/core/dev.c:5895
 gro_normal_list include/net/gro.h:515 [inline]
 napi_complete_done+0x3f2/0x990 net/core/dev.c:6246
 e1000_clean+0x1fa4/0x5e50 drivers/net/ethernet/intel/e1000/e1000_main.c:3808
 __napi_poll+0xd9/0x990 net/core/dev.c:6771
 napi_poll net/core/dev.c:6840 [inline]
 net_rx_action+0x90f/0x17e0 net/core/dev.c:6962
 handle_softirqs+0x152/0x6b0 kernel/softirq.c:554
 __do_softirq kernel/softirq.c:588 [inline]
 invoke_softirq kernel/softirq.c:428 [inline]
 __irq_exit_rcu kernel/softirq.c:637 [inline]
 irq_exit_rcu+0x5d/0x120 kernel/softirq.c:649
 common_interrupt+0x83/0x90 arch/x86/kernel/irq.c:278
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693

CPU: 0 PID: 239 Comm: modprobe Tainted: G    B              6.10.0-rc7-01816-g852e42cc2dd4 #3 1107521f0c7b55c9309062382d0bda9f604dbb6d
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014

Fixes: 06b22ef ("net/tcp: Wire TCP-AO to request sockets")
Reported-by: syzkaller <[email protected]>
Signed-off-by: Kuniyuki Iwashima <[email protected]>
Reviewed-by: Eric Dumazet <[email protected]>
Acked-by: Dmitry Safonov <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Paolo Abeni <[email protected]>
kdave pushed a commit that referenced this pull request Jul 18, 2024
The input subsystem registers LEDs with default triggers while holding
the input_lock and input_register_handler() takes the input_lock this
means that a triggers activate method cannot directly call
input_register_handler() as the old ledtrig-input-events code is doing.

The initial implementation of the input-events trigger mainly did not use
the simple LED trigger mechanism because that mechanism had an issue with
the initial state of a newly activated LED not matching the last
led_trigger_event() call for the trigger. This issue has been fixed in
commit 822c91e ("leds: trigger: Store brightness set by
led_trigger_event()").

Rewrite the "input-events" trigger to use the simple LED trigger mechanism,
registering a single input_handler at module_init() time and using
led_trigger_event() to set the brightness for all LEDs controlled by this
trigger.

Compared to the old code this looses the ability for the user to configure
a different brightness for the on state then LED_FULL, this is standard for
simple LED triggers and since this trigger is only in for-leds-next ATM
losing that functionality is not a regression.

This also changes the configurability of the LED off timeout from a per
LED setting to a global setting (runtime modifiable module-parameter).

Switching to registering a single input_handler at module_init() time fixes
the following locking issue reported by lockdep:

[ 2840.220145] usb 1-1.3: new low-speed USB device number 3 using xhci_hcd
[ 2840.307172] usb 1-1.3: New USB device found, idVendor=0603, idProduct=0002, bcdDevice= 2.21
[ 2840.307375] usb 1-1.3: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[ 2840.307423] usb 1-1.3: Product: USB Composite Device
[ 2840.307456] usb 1-1.3: Manufacturer: SINO WEALTH
[ 2840.333985] input: SINO WEALTH USB Composite Device as /devices/pci0000:00/0000:00:14.0/usb1/1-1/1-1.3/1-1.3:1.0/0003:0603:0002.0007/input/input19

[ 2840.386545] ======================================================
[ 2840.386549] WARNING: possible circular locking dependency detected
[ 2840.386554] 6.10.0-rc1+ torvalds#97 Tainted: G         C  E
[ 2840.386558] ------------------------------------------------------
[ 2840.386562] kworker/1:1/52 is trying to acquire lock:
[ 2840.386566] ffff98fcf1629300 (&led_cdev->led_access){+.+.}-{3:3}, at: led_classdev_register_ext+0x1c6/0x380
[ 2840.386590]
               but task is already holding lock:
[ 2840.386593] ffffffff88130cc8 (input_mutex){+.+.}-{3:3}, at: input_register_device.cold+0x47/0x150
[ 2840.386608]
               which lock already depends on the new lock.

[ 2840.386611]
               the existing dependency chain (in reverse order) is:
[ 2840.386615]
               -> #3 (input_mutex){+.+.}-{3:3}:
[ 2840.386624]        __mutex_lock+0x8c/0xc10
[ 2840.386634]        input_register_handler+0x1c/0xf0
[ 2840.386641]        0xffffffffc142c437
[ 2840.386655]        led_trigger_set+0x1e1/0x2e0
[ 2840.386661]        led_trigger_register+0x170/0x1b0
[ 2840.386666]        do_one_initcall+0x5e/0x3a0
[ 2840.386675]        do_init_module+0x60/0x220
[ 2840.386683]        __do_sys_init_module+0x15f/0x190
[ 2840.386689]        do_syscall_64+0x93/0x180
[ 2840.386696]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 2840.386705]
               -> #2 (&led_cdev->trigger_lock){+.+.}-{3:3}:
[ 2840.386714]        down_write+0x3b/0xd0
[ 2840.386720]        led_trigger_register+0x12c/0x1b0
[ 2840.386725]        rfkill_register+0xec/0x340 [rfkill]
[ 2840.386739]        wiphy_register+0x82a/0x930 [cfg80211]
[ 2840.386907]        brcmf_cfg80211_attach+0xcbd/0x1430 [brcmfmac]
[ 2840.386952]        brcmf_attach+0x1ba/0x4c0 [brcmfmac]
[ 2840.386991]        brcmf_pcie_setup+0x899/0xc70 [brcmfmac]
[ 2840.387030]        brcmf_fw_request_done+0x13b/0x180 [brcmfmac]
[ 2840.387070]        request_firmware_work_func+0x3b/0x70
[ 2840.387078]        process_one_work+0x21a/0x590
[ 2840.387085]        worker_thread+0x1d1/0x3e0
[ 2840.387090]        kthread+0xee/0x120
[ 2840.387096]        ret_from_fork+0x30/0x50
[ 2840.387105]        ret_from_fork_asm+0x1a/0x30
[ 2840.387112]
               -> #1 (leds_list_lock){++++}-{3:3}:
[ 2840.387123]        down_write+0x3b/0xd0
[ 2840.387129]        led_classdev_register_ext+0x29e/0x380
[ 2840.387134]        0xffffffffc0e6b74c
[ 2840.387143]        platform_probe+0x40/0xa0
[ 2840.387151]        really_probe+0xde/0x340
[ 2840.387157]        __driver_probe_device+0x78/0x110
[ 2840.387162]        driver_probe_device+0x1f/0xa0
[ 2840.387168]        __driver_attach+0xba/0x1c0
[ 2840.387173]        bus_for_each_dev+0x6b/0xb0
[ 2840.387180]        bus_add_driver+0x111/0x1f0
[ 2840.387185]        driver_register+0x6e/0xc0
[ 2840.387191]        do_one_initcall+0x5e/0x3a0
[ 2840.387197]        do_init_module+0x60/0x220
[ 2840.387204]        __do_sys_init_module+0x15f/0x190
[ 2840.387210]        do_syscall_64+0x93/0x180
[ 2840.387217]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 2840.387224]
               -> #0 (&led_cdev->led_access){+.+.}-{3:3}:
[ 2840.387233]        __lock_acquire+0x11c6/0x1f20
[ 2840.387239]        lock_acquire+0xc8/0x2b0
[ 2840.387244]        __mutex_lock+0x8c/0xc10
[ 2840.387251]        led_classdev_register_ext+0x1c6/0x380
[ 2840.387256]        input_leds_connect+0x139/0x260
[ 2840.387262]        input_attach_handler.isra.0+0x75/0x90
[ 2840.387268]        input_register_device.cold+0xa1/0x150
[ 2840.387274]        hidinput_connect+0x848/0xb00
[ 2840.387280]        hid_connect+0x567/0x5a0
[ 2840.387288]        hid_hw_start+0x3f/0x60
[ 2840.387294]        hid_device_probe+0x10d/0x190
[ 2840.387298]        really_probe+0xde/0x340
[ 2840.387304]        __driver_probe_device+0x78/0x110
[ 2840.387309]        driver_probe_device+0x1f/0xa0
[ 2840.387314]        __device_attach_driver+0x85/0x110
[ 2840.387320]        bus_for_each_drv+0x78/0xc0
[ 2840.387326]        __device_attach+0xb0/0x1b0
[ 2840.387332]        bus_probe_device+0x94/0xb0
[ 2840.387337]        device_add+0x64a/0x860
[ 2840.387343]        hid_add_device+0xe5/0x240
[ 2840.387349]        usbhid_probe+0x4bb/0x600
[ 2840.387356]        usb_probe_interface+0xea/0x2b0
[ 2840.387363]        really_probe+0xde/0x340
[ 2840.387368]        __driver_probe_device+0x78/0x110
[ 2840.387373]        driver_probe_device+0x1f/0xa0
[ 2840.387378]        __device_attach_driver+0x85/0x110
[ 2840.387383]        bus_for_each_drv+0x78/0xc0
[ 2840.387390]        __device_attach+0xb0/0x1b0
[ 2840.387395]        bus_probe_device+0x94/0xb0
[ 2840.387400]        device_add+0x64a/0x860
[ 2840.387405]        usb_set_configuration+0x5e8/0x880
[ 2840.387411]        usb_generic_driver_probe+0x3e/0x60
[ 2840.387418]        usb_probe_device+0x3d/0x120
[ 2840.387423]        really_probe+0xde/0x340
[ 2840.387428]        __driver_probe_device+0x78/0x110
[ 2840.387434]        driver_probe_device+0x1f/0xa0
[ 2840.387439]        __device_attach_driver+0x85/0x110
[ 2840.387444]        bus_for_each_drv+0x78/0xc0
[ 2840.387451]        __device_attach+0xb0/0x1b0
[ 2840.387456]        bus_probe_device+0x94/0xb0
[ 2840.387461]        device_add+0x64a/0x860
[ 2840.387466]        usb_new_device.cold+0x141/0x38f
[ 2840.387473]        hub_event+0x1166/0x1980
[ 2840.387479]        process_one_work+0x21a/0x590
[ 2840.387484]        worker_thread+0x1d1/0x3e0
[ 2840.387488]        kthread+0xee/0x120
[ 2840.387493]        ret_from_fork+0x30/0x50
[ 2840.387500]        ret_from_fork_asm+0x1a/0x30
[ 2840.387506]
               other info that might help us debug this:

[ 2840.387509] Chain exists of:
                 &led_cdev->led_access --> &led_cdev->trigger_lock --> input_mutex

[ 2840.387520]  Possible unsafe locking scenario:

[ 2840.387523]        CPU0                    CPU1
[ 2840.387526]        ----                    ----
[ 2840.387529]   lock(input_mutex);
[ 2840.387534]                                lock(&led_cdev->trigger_lock);
[ 2840.387540]                                lock(input_mutex);
[ 2840.387545]   lock(&led_cdev->led_access);
[ 2840.387550]
                *** DEADLOCK ***

[ 2840.387552] 7 locks held by kworker/1:1/52:
[ 2840.387557]  #0: ffff98fcc1d07148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x4af/0x590
[ 2840.387570]  #1: ffffb67e00213e60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x1d5/0x590
[ 2840.387583]  #2: ffff98fcc6582190 (&dev->mutex){....}-{3:3}, at: hub_event+0x57/0x1980
[ 2840.387596]  #3: ffff98fccb3c6990 (&dev->mutex){....}-{3:3}, at: __device_attach+0x26/0x1b0
[ 2840.387610]  #4: ffff98fcc5260960 (&dev->mutex){....}-{3:3}, at: __device_attach+0x26/0x1b0
[ 2840.387622]  #5: ffff98fce3999a20 (&dev->mutex){....}-{3:3}, at: __device_attach+0x26/0x1b0
[ 2840.387635]  #6: ffffffff88130cc8 (input_mutex){+.+.}-{3:3}, at: input_register_device.cold+0x47/0x150
[ 2840.387649]
               stack backtrace:
[ 2840.387653] CPU: 1 PID: 52 Comm: kworker/1:1 Tainted: G         C  E      6.10.0-rc1+ torvalds#97
[ 2840.387659] Hardware name: Xiaomi Inc Mipad2/Mipad, BIOS MIPad-P4.X64.0043.R03.1603071414 03/07/2016
[ 2840.387665] Workqueue: usb_hub_wq hub_event
[ 2840.387674] Call Trace:
[ 2840.387681]  <TASK>
[ 2840.387689]  dump_stack_lvl+0x68/0x90
[ 2840.387700]  check_noncircular+0x10d/0x120
[ 2840.387710]  ? register_lock_class+0x38/0x480
[ 2840.387717]  ? check_noncircular+0x74/0x120
[ 2840.387727]  __lock_acquire+0x11c6/0x1f20
[ 2840.387736]  lock_acquire+0xc8/0x2b0
[ 2840.387743]  ? led_classdev_register_ext+0x1c6/0x380
[ 2840.387753]  __mutex_lock+0x8c/0xc10
[ 2840.387760]  ? led_classdev_register_ext+0x1c6/0x380
[ 2840.387766]  ? _raw_spin_unlock_irqrestore+0x35/0x60
[ 2840.387773]  ? klist_next+0x158/0x160
[ 2840.387781]  ? led_classdev_register_ext+0x1c6/0x380
[ 2840.387787]  ? lockdep_init_map_type+0x58/0x250
[ 2840.387796]  ? led_classdev_register_ext+0x1c6/0x380
[ 2840.387802]  led_classdev_register_ext+0x1c6/0x380
[ 2840.387810]  ? kvasprintf+0x70/0xb0
[ 2840.387820]  ? kasprintf+0x3e/0x50
[ 2840.387829]  input_leds_connect+0x139/0x260
[ 2840.387838]  input_attach_handler.isra.0+0x75/0x90
[ 2840.387846]  input_register_device.cold+0xa1/0x150
[ 2840.387854]  hidinput_connect+0x848/0xb00
[ 2840.387862]  ? usbhid_start+0x45b/0x7b0
[ 2840.387870]  hid_connect+0x567/0x5a0
[ 2840.387878]  ? __mutex_unlock_slowpath+0x2d/0x260
[ 2840.387891]  hid_hw_start+0x3f/0x60
[ 2840.387899]  hid_device_probe+0x10d/0x190
[ 2840.387906]  ? __pfx___device_attach_driver+0x10/0x10
[ 2840.387913]  really_probe+0xde/0x340
[ 2840.387919]  ? pm_runtime_barrier+0x50/0x90
[ 2840.387927]  __driver_probe_device+0x78/0x110
[ 2840.387934]  driver_probe_device+0x1f/0xa0
[ 2840.387941]  __device_attach_driver+0x85/0x110
[ 2840.387949]  bus_for_each_drv+0x78/0xc0
[ 2840.387959]  __device_attach+0xb0/0x1b0
[ 2840.387967]  bus_probe_device+0x94/0xb0
[ 2840.387974]  device_add+0x64a/0x860
[ 2840.387982]  ? __debugfs_create_file+0x14a/0x1c0
[ 2840.387993]  hid_add_device+0xe5/0x240
[ 2840.388002]  usbhid_probe+0x4bb/0x600
[ 2840.388013]  usb_probe_interface+0xea/0x2b0
[ 2840.388021]  ? __pfx___device_attach_driver+0x10/0x10
[ 2840.388028]  really_probe+0xde/0x340
[ 2840.388034]  ? pm_runtime_barrier+0x50/0x90
[ 2840.388040]  __driver_probe_device+0x78/0x110
[ 2840.388048]  driver_probe_device+0x1f/0xa0
[ 2840.388055]  __device_attach_driver+0x85/0x110
[ 2840.388062]  bus_for_each_drv+0x78/0xc0
[ 2840.388071]  __device_attach+0xb0/0x1b0
[ 2840.388079]  bus_probe_device+0x94/0xb0
[ 2840.388086]  device_add+0x64a/0x860
[ 2840.388094]  ? __mutex_unlock_slowpath+0x2d/0x260
[ 2840.388103]  usb_set_configuration+0x5e8/0x880
[ 2840.388114]  ? __pfx___device_attach_driver+0x10/0x10
[ 2840.388121]  usb_generic_driver_probe+0x3e/0x60
[ 2840.388129]  usb_probe_device+0x3d/0x120
[ 2840.388137]  really_probe+0xde/0x340
[ 2840.388142]  ? pm_runtime_barrier+0x50/0x90
[ 2840.388149]  __driver_probe_device+0x78/0x110
[ 2840.388156]  driver_probe_device+0x1f/0xa0
[ 2840.388163]  __device_attach_driver+0x85/0x110
[ 2840.388171]  bus_for_each_drv+0x78/0xc0
[ 2840.388180]  __device_attach+0xb0/0x1b0
[ 2840.388188]  bus_probe_device+0x94/0xb0
[ 2840.388195]  device_add+0x64a/0x860
[ 2840.388202]  ? lockdep_hardirqs_on+0x78/0x100
[ 2840.388210]  ? _raw_spin_unlock_irqrestore+0x35/0x60
[ 2840.388219]  usb_new_device.cold+0x141/0x38f
[ 2840.388227]  hub_event+0x1166/0x1980
[ 2840.388242]  process_one_work+0x21a/0x590
[ 2840.388249]  ? move_linked_works+0x70/0xa0
[ 2840.388260]  worker_thread+0x1d1/0x3e0
[ 2840.388268]  ? __pfx_worker_thread+0x10/0x10
[ 2840.388273]  kthread+0xee/0x120
[ 2840.388279]  ? __pfx_kthread+0x10/0x10
[ 2840.388287]  ret_from_fork+0x30/0x50
[ 2840.388294]  ? __pfx_kthread+0x10/0x10
[ 2840.388301]  ret_from_fork_asm+0x1a/0x30
[ 2840.388315]  </TASK>
[ 2840.415630] hid-generic 0003:0603:0002.0007: input,hidraw6: USB HID v1.10 Keyboard [SINO WEALTH USB Composite Device] on usb-0000:00:14.0-1.3/input0

Signed-off-by: Hans de Goede <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Lee Jones <[email protected]>
kdave pushed a commit that referenced this pull request Jul 19, 2024
Test case: 2 threads write short inline data to a file.
In ext4_page_mkwrite the resulting inline data is converted.
Handling ext4_grp_locked_error with description "block bitmap
and bg descriptor inconsistent: X vs Y free clusters" calls
ext4_force_shutdown. The conversion clears
EXT4_STATE_MAY_INLINE_DATA but fails for
ext4_destroy_inline_data_nolock and ext4_mark_iloc_dirty due
to ext4_forced_shutdown. The restoration of inline data fails
for the same reason not setting EXT4_STATE_MAY_INLINE_DATA.
Without the flag set a regular process path in ext4_da_write_end
follows trying to dereference page folio private pointer that has
not been set. The fix calls early return with -EIO error shall the
pointer to private be NULL.

Sample crash report:

Unable to handle kernel paging request at virtual address dfff800000000004
KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027]
Mem abort info:
  ESR = 0x0000000096000005
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x05: level 1 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000
  CM = 0, WnR = 0, TnD = 0, TagAccess = 0
  GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[dfff800000000004] address between user and kernel address ranges
Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 20274 Comm: syz-executor185 Not tainted 6.9.0-rc7-syzkaller-gfda5695d692c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : __block_commit_write+0x64/0x2b0 fs/buffer.c:2167
lr : __block_commit_write+0x3c/0x2b0 fs/buffer.c:2160
sp : ffff8000a1957600
x29: ffff8000a1957610 x28: dfff800000000000 x27: ffff0000e30e34b0
x26: 0000000000000000 x25: dfff800000000000 x24: dfff800000000000
x23: fffffdffc397c9e0 x22: 0000000000000020 x21: 0000000000000020
x20: 0000000000000040 x19: fffffdffc397c9c0 x18: 1fffe000367bd196
x17: ffff80008eead000 x16: ffff80008ae89e3c x15: 00000000200000c0
x14: 1fffe0001cbe4e04 x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000000001 x10: 0000000000ff0100 x9 : 0000000000000000
x8 : 0000000000000004 x7 : 0000000000000000 x6 : 0000000000000000
x5 : fffffdffc397c9c0 x4 : 0000000000000020 x3 : 0000000000000020
x2 : 0000000000000040 x1 : 0000000000000020 x0 : fffffdffc397c9c0
Call trace:
 __block_commit_write+0x64/0x2b0 fs/buffer.c:2167
 block_write_end+0xb4/0x104 fs/buffer.c:2253
 ext4_da_do_write_end fs/ext4/inode.c:2955 [inline]
 ext4_da_write_end+0x2c4/0xa40 fs/ext4/inode.c:3028
 generic_perform_write+0x394/0x588 mm/filemap.c:3985
 ext4_buffered_write_iter+0x2c0/0x4ec fs/ext4/file.c:299
 ext4_file_write_iter+0x188/0x1780
 call_write_iter include/linux/fs.h:2110 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x968/0xc3c fs/read_write.c:590
 ksys_write+0x15c/0x26c fs/read_write.c:643
 __do_sys_write fs/read_write.c:655 [inline]
 __se_sys_write fs/read_write.c:652 [inline]
 __arm64_sys_write+0x7c/0x90 fs/read_write.c:652
 __invoke_syscall arch/arm64/kernel/syscall.c:34 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:48
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:133
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:152
 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:712
 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730
 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598
Code: 97f85911 f94002da 91008356 d343fec8 (38796908)
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	97f85911 	bl	0xffffffffffe16444
   4:	f94002da 	ldr	x26, [x22]
   8:	91008356 	add	x22, x26, #0x20
   c:	d343fec8 	lsr	x8, x22, #3
* 10:	38796908 	ldrb	w8, [x8, x25] <-- trapping instruction

Reported-by: [email protected]
Closes: https://syzkaller.appspot.com/bug?extid=18df508cf00a0598d9a6
Link: https://lore.kernel.org/all/[email protected]/T/
Signed-off-by: Wojciech Gładysz <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Theodore Ts'o <[email protected]>
kdave pushed a commit that referenced this pull request Aug 9, 2024
When l2tp tunnels use a socket provided by userspace, we can hit
lockdep splats like the below when data is transmitted through another
(unrelated) userspace socket which then gets routed over l2tp.

This issue was previously discussed here:
https://lore.kernel.org/netdev/[email protected]/

The solution is to have lockdep treat socket locks of l2tp tunnel
sockets separately than those of standard INET sockets. To do so, use
a different lockdep subclass where lock nesting is possible.

  ============================================
  WARNING: possible recursive locking detected
  6.10.0+ torvalds#34 Not tainted
  --------------------------------------------
  iperf3/771 is trying to acquire lock:
  ffff8881027601d8 (slock-AF_INET/1){+.-.}-{2:2}, at: l2tp_xmit_skb+0x243/0x9d0

  but task is already holding lock:
  ffff888102650d98 (slock-AF_INET/1){+.-.}-{2:2}, at: tcp_v4_rcv+0x1848/0x1e10

  other info that might help us debug this:
   Possible unsafe locking scenario:

         CPU0
         ----
    lock(slock-AF_INET/1);
    lock(slock-AF_INET/1);

   *** DEADLOCK ***

   May be due to missing lock nesting notation

  10 locks held by iperf3/771:
   #0: ffff888102650258 (sk_lock-AF_INET){+.+.}-{0:0}, at: tcp_sendmsg+0x1a/0x40
   #1: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: __ip_queue_xmit+0x4b/0xbc0
   #2: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x17a/0x1130
   #3: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x28b/0x9f0
   #4: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: ip_local_deliver_finish+0xf9/0x260
   #5: ffff888102650d98 (slock-AF_INET/1){+.-.}-{2:2}, at: tcp_v4_rcv+0x1848/0x1e10
   #6: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: __ip_queue_xmit+0x4b/0xbc0
   #7: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x17a/0x1130
   #8: ffffffff822ac1e0 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0xcc/0x1450
   #9: ffff888101f33258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#2){+...}-{2:2}, at: __dev_queue_xmit+0x513/0x1450

  stack backtrace:
  CPU: 2 UID: 0 PID: 771 Comm: iperf3 Not tainted 6.10.0+ torvalds#34
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
  Call Trace:
   <IRQ>
   dump_stack_lvl+0x69/0xa0
   dump_stack+0xc/0x20
   __lock_acquire+0x135d/0x2600
   ? srso_alias_return_thunk+0x5/0xfbef5
   lock_acquire+0xc4/0x2a0
   ? l2tp_xmit_skb+0x243/0x9d0
   ? __skb_checksum+0xa3/0x540
   _raw_spin_lock_nested+0x35/0x50
   ? l2tp_xmit_skb+0x243/0x9d0
   l2tp_xmit_skb+0x243/0x9d0
   l2tp_eth_dev_xmit+0x3c/0xc0
   dev_hard_start_xmit+0x11e/0x420
   sch_direct_xmit+0xc3/0x640
   __dev_queue_xmit+0x61c/0x1450
   ? ip_finish_output2+0xf4c/0x1130
   ip_finish_output2+0x6b6/0x1130
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __ip_finish_output+0x217/0x380
   ? srso_alias_return_thunk+0x5/0xfbef5
   __ip_finish_output+0x217/0x380
   ip_output+0x99/0x120
   __ip_queue_xmit+0xae4/0xbc0
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? tcp_options_write.constprop.0+0xcb/0x3e0
   ip_queue_xmit+0x34/0x40
   __tcp_transmit_skb+0x1625/0x1890
   __tcp_send_ack+0x1b8/0x340
   tcp_send_ack+0x23/0x30
   __tcp_ack_snd_check+0xa8/0x530
   ? srso_alias_return_thunk+0x5/0xfbef5
   tcp_rcv_established+0x412/0xd70
   tcp_v4_do_rcv+0x299/0x420
   tcp_v4_rcv+0x1991/0x1e10
   ip_protocol_deliver_rcu+0x50/0x220
   ip_local_deliver_finish+0x158/0x260
   ip_local_deliver+0xc8/0xe0
   ip_rcv+0xe5/0x1d0
   ? __pfx_ip_rcv+0x10/0x10
   __netif_receive_skb_one_core+0xce/0xe0
   ? process_backlog+0x28b/0x9f0
   __netif_receive_skb+0x34/0xd0
   ? process_backlog+0x28b/0x9f0
   process_backlog+0x2cb/0x9f0
   __napi_poll.constprop.0+0x61/0x280
   net_rx_action+0x332/0x670
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? find_held_lock+0x2b/0x80
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   handle_softirqs+0xda/0x480
   ? __dev_queue_xmit+0xa2c/0x1450
   do_softirq+0xa1/0xd0
   </IRQ>
   <TASK>
   __local_bh_enable_ip+0xc8/0xe0
   ? __dev_queue_xmit+0xa2c/0x1450
   __dev_queue_xmit+0xa48/0x1450
   ? ip_finish_output2+0xf4c/0x1130
   ip_finish_output2+0x6b6/0x1130
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __ip_finish_output+0x217/0x380
   ? srso_alias_return_thunk+0x5/0xfbef5
   __ip_finish_output+0x217/0x380
   ip_output+0x99/0x120
   __ip_queue_xmit+0xae4/0xbc0
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? tcp_options_write.constprop.0+0xcb/0x3e0
   ip_queue_xmit+0x34/0x40
   __tcp_transmit_skb+0x1625/0x1890
   tcp_write_xmit+0x766/0x2fb0
   ? __entry_text_end+0x102ba9/0x102bad
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __might_fault+0x74/0xc0
   ? srso_alias_return_thunk+0x5/0xfbef5
   __tcp_push_pending_frames+0x56/0x190
   tcp_push+0x117/0x310
   tcp_sendmsg_locked+0x14c1/0x1740
   tcp_sendmsg+0x28/0x40
   inet_sendmsg+0x5d/0x90
   sock_write_iter+0x242/0x2b0
   vfs_write+0x68d/0x800
   ? __pfx_sock_write_iter+0x10/0x10
   ksys_write+0xc8/0xf0
   __x64_sys_write+0x3d/0x50
   x64_sys_call+0xfaf/0x1f50
   do_syscall_64+0x6d/0x140
   entry_SYSCALL_64_after_hwframe+0x76/0x7e
  RIP: 0033:0x7f4d143af992
  Code: c3 8b 07 85 c0 75 24 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> e9 01 cc ff ff 41 54 b8 02 00 00 0
  RSP: 002b:00007ffd65032058 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
  RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f4d143af992
  RDX: 0000000000000025 RSI: 00007f4d143f3bcc RDI: 0000000000000005
  RBP: 00007f4d143f2b28 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4d143f3bcc
  R13: 0000000000000005 R14: 0000000000000000 R15: 00007ffd650323f0
   </TASK>

Fixes: 0b2c597 ("l2tp: close all race conditions in l2tp_tunnel_register()")
Suggested-by: Eric Dumazet <[email protected]>
Reported-by: [email protected]
Closes: https://syzkaller.appspot.com/bug?extid=6acef9e0a4d1f46c83d4
CC: [email protected]
CC: [email protected]
Signed-off-by: James Chapman <[email protected]>
Signed-off-by: Tom Parkin <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
kdave pushed a commit that referenced this pull request Aug 18, 2024
Lockdep reported a warning in Linux version 6.6:

[  414.344659] ================================
[  414.345155] WARNING: inconsistent lock state
[  414.345658] 6.6.0-07439-gba2303cacfda #6 Not tainted
[  414.346221] --------------------------------
[  414.346712] inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage.
[  414.347545] kworker/u10:3/1152 [HC0[0]:SC0[0]:HE0:SE1] takes:
[  414.349245] ffff88810edd1098 (&sbq->ws[i].wait){+.?.}-{2:2}, at: blk_mq_dispatch_rq_list+0x131c/0x1ee0
[  414.351204] {IN-SOFTIRQ-W} state was registered at:
[  414.351751]   lock_acquire+0x18d/0x460
[  414.352218]   _raw_spin_lock_irqsave+0x39/0x60
[  414.352769]   __wake_up_common_lock+0x22/0x60
[  414.353289]   sbitmap_queue_wake_up+0x375/0x4f0
[  414.353829]   sbitmap_queue_clear+0xdd/0x270
[  414.354338]   blk_mq_put_tag+0xdf/0x170
[  414.354807]   __blk_mq_free_request+0x381/0x4d0
[  414.355335]   blk_mq_free_request+0x28b/0x3e0
[  414.355847]   __blk_mq_end_request+0x242/0xc30
[  414.356367]   scsi_end_request+0x2c1/0x830
[  414.345155] WARNING: inconsistent lock state
[  414.345658] 6.6.0-07439-gba2303cacfda #6 Not tainted
[  414.346221] --------------------------------
[  414.346712] inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage.
[  414.347545] kworker/u10:3/1152 [HC0[0]:SC0[0]:HE0:SE1] takes:
[  414.349245] ffff88810edd1098 (&sbq->ws[i].wait){+.?.}-{2:2}, at: blk_mq_dispatch_rq_list+0x131c/0x1ee0
[  414.351204] {IN-SOFTIRQ-W} state was registered at:
[  414.351751]   lock_acquire+0x18d/0x460
[  414.352218]   _raw_spin_lock_irqsave+0x39/0x60
[  414.352769]   __wake_up_common_lock+0x22/0x60
[  414.353289]   sbitmap_queue_wake_up+0x375/0x4f0
[  414.353829]   sbitmap_queue_clear+0xdd/0x270
[  414.354338]   blk_mq_put_tag+0xdf/0x170
[  414.354807]   __blk_mq_free_request+0x381/0x4d0
[  414.355335]   blk_mq_free_request+0x28b/0x3e0
[  414.355847]   __blk_mq_end_request+0x242/0xc30
[  414.356367]   scsi_end_request+0x2c1/0x830
[  414.356863]   scsi_io_completion+0x177/0x1610
[  414.357379]   scsi_complete+0x12f/0x260
[  414.357856]   blk_complete_reqs+0xba/0xf0
[  414.358338]   __do_softirq+0x1b0/0x7a2
[  414.358796]   irq_exit_rcu+0x14b/0x1a0
[  414.359262]   sysvec_call_function_single+0xaf/0xc0
[  414.359828]   asm_sysvec_call_function_single+0x1a/0x20
[  414.360426]   default_idle+0x1e/0x30
[  414.360873]   default_idle_call+0x9b/0x1f0
[  414.361390]   do_idle+0x2d2/0x3e0
[  414.361819]   cpu_startup_entry+0x55/0x60
[  414.362314]   start_secondary+0x235/0x2b0
[  414.362809]   secondary_startup_64_no_verify+0x18f/0x19b
[  414.363413] irq event stamp: 428794
[  414.363825] hardirqs last  enabled at (428793): [<ffffffff816bfd1c>] ktime_get+0x1dc/0x200
[  414.364694] hardirqs last disabled at (428794): [<ffffffff85470177>] _raw_spin_lock_irq+0x47/0x50
[  414.365629] softirqs last  enabled at (428444): [<ffffffff85474780>] __do_softirq+0x540/0x7a2
[  414.366522] softirqs last disabled at (428419): [<ffffffff813f65ab>] irq_exit_rcu+0x14b/0x1a0
[  414.367425]
               other info that might help us debug this:
[  414.368194]  Possible unsafe locking scenario:
[  414.368900]        CPU0
[  414.369225]        ----
[  414.369548]   lock(&sbq->ws[i].wait);
[  414.370000]   <Interrupt>
[  414.370342]     lock(&sbq->ws[i].wait);
[  414.370802]
                *** DEADLOCK ***
[  414.371569] 5 locks held by kworker/u10:3/1152:
[  414.372088]  #0: ffff88810130e938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x357/0x13f0
[  414.373180]  #1: ffff88810201fdb8 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x3a3/0x13f0
[  414.374384]  #2: ffffffff86ffbdc0 (rcu_read_lock){....}-{1:2}, at: blk_mq_run_hw_queue+0x637/0xa00
[  414.375342]  #3: ffff88810edd1098 (&sbq->ws[i].wait){+.?.}-{2:2}, at: blk_mq_dispatch_rq_list+0x131c/0x1ee0
[  414.376377]  #4: ffff888106205a08 (&hctx->dispatch_wait_lock){+.-.}-{2:2}, at: blk_mq_dispatch_rq_list+0x1337/0x1ee0
[  414.378607]
               stack backtrace:
[  414.379177] CPU: 0 PID: 1152 Comm: kworker/u10:3 Not tainted 6.6.0-07439-gba2303cacfda #6
[  414.380032] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
[  414.381177] Workqueue: writeback wb_workfn (flush-253:0)
[  414.381805] Call Trace:
[  414.382136]  <TASK>
[  414.382429]  dump_stack_lvl+0x91/0xf0
[  414.382884]  mark_lock_irq+0xb3b/0x1260
[  414.383367]  ? __pfx_mark_lock_irq+0x10/0x10
[  414.383889]  ? stack_trace_save+0x8e/0xc0
[  414.384373]  ? __pfx_stack_trace_save+0x10/0x10
[  414.384903]  ? graph_lock+0xcf/0x410
[  414.385350]  ? save_trace+0x3d/0xc70
[  414.385808]  mark_lock.part.20+0x56d/0xa90
[  414.386317]  mark_held_locks+0xb0/0x110
[  414.386791]  ? __pfx_do_raw_spin_lock+0x10/0x10
[  414.387320]  lockdep_hardirqs_on_prepare+0x297/0x3f0
[  414.387901]  ? _raw_spin_unlock_irq+0x28/0x50
[  414.388422]  trace_hardirqs_on+0x58/0x100
[  414.388917]  _raw_spin_unlock_irq+0x28/0x50
[  414.389422]  __blk_mq_tag_busy+0x1d6/0x2a0
[  414.389920]  __blk_mq_get_driver_tag+0x761/0x9f0
[  414.390899]  blk_mq_dispatch_rq_list+0x1780/0x1ee0
[  414.391473]  ? __pfx_blk_mq_dispatch_rq_list+0x10/0x10
[  414.392070]  ? sbitmap_get+0x2b8/0x450
[  414.392533]  ? __blk_mq_get_driver_tag+0x210/0x9f0
[  414.393095]  __blk_mq_sched_dispatch_requests+0xd99/0x1690
[  414.393730]  ? elv_attempt_insert_merge+0x1b1/0x420
[  414.394302]  ? __pfx___blk_mq_sched_dispatch_requests+0x10/0x10
[  414.394970]  ? lock_acquire+0x18d/0x460
[  414.395456]  ? blk_mq_run_hw_queue+0x637/0xa00
[  414.395986]  ? __pfx_lock_acquire+0x10/0x10
[  414.396499]  blk_mq_sched_dispatch_requests+0x109/0x190
[  414.397100]  blk_mq_run_hw_queue+0x66e/0xa00
[  414.397616]  blk_mq_flush_plug_list.part.17+0x614/0x2030
[  414.398244]  ? __pfx_blk_mq_flush_plug_list.part.17+0x10/0x10
[  414.398897]  ? writeback_sb_inodes+0x241/0xcc0
[  414.399429]  blk_mq_flush_plug_list+0x65/0x80
[  414.399957]  __blk_flush_plug+0x2f1/0x530
[  414.400458]  ? __pfx___blk_flush_plug+0x10/0x10
[  414.400999]  blk_finish_plug+0x59/0xa0
[  414.401467]  wb_writeback+0x7cc/0x920
[  414.401935]  ? __pfx_wb_writeback+0x10/0x10
[  414.402442]  ? mark_held_locks+0xb0/0x110
[  414.402931]  ? __pfx_do_raw_spin_lock+0x10/0x10
[  414.403462]  ? lockdep_hardirqs_on_prepare+0x297/0x3f0
[  414.404062]  wb_workfn+0x2b3/0xcf0
[  414.404500]  ? __pfx_wb_workfn+0x10/0x10
[  414.404989]  process_scheduled_works+0x432/0x13f0
[  414.405546]  ? __pfx_process_scheduled_works+0x10/0x10
[  414.406139]  ? do_raw_spin_lock+0x101/0x2a0
[  414.406641]  ? assign_work+0x19b/0x240
[  414.407106]  ? lock_is_held_type+0x9d/0x110
[  414.407604]  worker_thread+0x6f2/0x1160
[  414.408075]  ? __kthread_parkme+0x62/0x210
[  414.408572]  ? lockdep_hardirqs_on_prepare+0x297/0x3f0
[  414.409168]  ? __kthread_parkme+0x13c/0x210
[  414.409678]  ? __pfx_worker_thread+0x10/0x10
[  414.410191]  kthread+0x33c/0x440
[  414.410602]  ? __pfx_kthread+0x10/0x10
[  414.411068]  ret_from_fork+0x4d/0x80
[  414.411526]  ? __pfx_kthread+0x10/0x10
[  414.411993]  ret_from_fork_asm+0x1b/0x30
[  414.412489]  </TASK>

When interrupt is turned on while a lock holding by spin_lock_irq it
throws a warning because of potential deadlock.

blk_mq_prep_dispatch_rq
 blk_mq_get_driver_tag
  __blk_mq_get_driver_tag
   __blk_mq_alloc_driver_tag
    blk_mq_tag_busy -> tag is already busy
    // failed to get driver tag
 blk_mq_mark_tag_wait
  spin_lock_irq(&wq->lock) -> lock A (&sbq->ws[i].wait)
  __add_wait_queue(wq, wait) -> wait queue active
  blk_mq_get_driver_tag
  __blk_mq_tag_busy
-> 1) tag must be idle, which means there can't be inflight IO
   spin_lock_irq(&tags->lock) -> lock B (hctx->tags)
   spin_unlock_irq(&tags->lock) -> unlock B, turn on interrupt accidentally
-> 2) context must be preempt by IO interrupt to trigger deadlock.

As shown above, the deadlock is not possible in theory, but the warning
still need to be fixed.

Fix it by using spin_lock_irqsave to get lockB instead of spin_lock_irq.

Fixes: 4f1731d ("blk-mq: fix potential io hang by wrong 'wake_batch'")
Signed-off-by: Li Lingfeng <[email protected]>
Reviewed-by: Ming Lei <[email protected]>
Reviewed-by: Yu Kuai <[email protected]>
Reviewed-by: Bart Van Assche <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
kdave pushed a commit that referenced this pull request Aug 25, 2024
…git/netfilter/nf

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

Patch #1 disable BH when collecting stats via hardware offload to ensure
         concurrent updates from packet path do not result in losing stats.
         From Sebastian Andrzej Siewior.

Patch #2 uses write seqcount to reset counters serialize against reader.
         Also from Sebastian Andrzej Siewior.

Patch #3 ensures vlan header is in place before accessing its fields,
         according to KMSAN splat triggered by syzbot.

* tag 'nf-24-08-22' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
  netfilter: flowtable: validate vlan header
  netfilter: nft_counter: Synchronize nft_counter_reset() against reader.
  netfilter: nft_counter: Disable BH in nft_counter_offload_stats().
====================

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
kdave pushed a commit that referenced this pull request Sep 17, 2024
Once the kthread is running and available
(i.e. @printk_kthreads_running is set), the kthread becomes
responsible for flushing any pending messages which are added
in NBCON_PRIO_NORMAL context. Namely the legacy
console_flush_all() and device_release() no longer flush the
console. And nbcon_atomic_flush_pending() used by
nbcon_cpu_emergency_exit() no longer flushes messages added
after the emergency messages.

The console context is safe when used by the kthread only when
one of the following conditions are true:

  1. Other caller acquires the console context with
     NBCON_PRIO_NORMAL with preemption disabled. It will
     release the context before rescheduling.

  2. Other caller acquires the console context with
     NBCON_PRIO_NORMAL under the device_lock.

  3. The kthread is the only context which acquires the console
     with NBCON_PRIO_NORMAL.

This is satisfied for all atomic printing call sites:

nbcon_legacy_emit_next_record() (#1)

nbcon_atomic_flush_pending_con() (#1)

nbcon_device_release() (#2)

It is even double guaranteed when @printk_kthreads_running
is set because then _only_ the kthread will print for
NBCON_PRIO_NORMAL. (#3)

Signed-off-by: John Ogness <[email protected]>
Reviewed-by: Petr Mladek <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Petr Mladek <[email protected]>
kdave pushed a commit that referenced this pull request Sep 23, 2024
Add nested locking with I_MUTEX_XATTR subclass to avoid lockdep warning
while handling xattr inode on file open syscall at ext4_xattr_inode_iget.

Backtrace
EXT4-fs (loop0): Ignoring removed oldalloc option
======================================================
WARNING: possible circular locking dependency detected
5.10.0-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor543/2794 is trying to acquire lock:
ffff8880215e1a48 (&ea_inode->i_rwsem#7/1){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:782 [inline]
ffff8880215e1a48 (&ea_inode->i_rwsem#7/1){+.+.}-{3:3}, at: ext4_xattr_inode_iget+0x42a/0x5c0 fs/ext4/xattr.c:425

but task is already holding lock:
ffff8880215e3278 (&ei->i_data_sem/3){++++}-{3:3}, at: ext4_setattr+0x136d/0x19c0 fs/ext4/inode.c:5559

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&ei->i_data_sem/3){++++}-{3:3}:
       lock_acquire+0x197/0x480 kernel/locking/lockdep.c:5566
       down_write+0x93/0x180 kernel/locking/rwsem.c:1564
       ext4_update_i_disksize fs/ext4/ext4.h:3267 [inline]
       ext4_xattr_inode_write fs/ext4/xattr.c:1390 [inline]
       ext4_xattr_inode_lookup_create fs/ext4/xattr.c:1538 [inline]
       ext4_xattr_set_entry+0x331a/0x3d80 fs/ext4/xattr.c:1662
       ext4_xattr_ibody_set+0x124/0x390 fs/ext4/xattr.c:2228
       ext4_xattr_set_handle+0xc27/0x14e0 fs/ext4/xattr.c:2385
       ext4_xattr_set+0x219/0x390 fs/ext4/xattr.c:2498
       ext4_xattr_user_set+0xc9/0xf0 fs/ext4/xattr_user.c:40
       __vfs_setxattr+0x404/0x450 fs/xattr.c:177
       __vfs_setxattr_noperm+0x11d/0x4f0 fs/xattr.c:208
       __vfs_setxattr_locked+0x1f9/0x210 fs/xattr.c:266
       vfs_setxattr+0x112/0x2c0 fs/xattr.c:283
       setxattr+0x1db/0x3e0 fs/xattr.c:548
       path_setxattr+0x15a/0x240 fs/xattr.c:567
       __do_sys_setxattr fs/xattr.c:582 [inline]
       __se_sys_setxattr fs/xattr.c:578 [inline]
       __x64_sys_setxattr+0xc5/0xe0 fs/xattr.c:578
       do_syscall_64+0x6d/0xa0 arch/x86/entry/common.c:62
       entry_SYSCALL_64_after_hwframe+0x61/0xcb

-> #0 (&ea_inode->i_rwsem#7/1){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:2988 [inline]
       check_prevs_add kernel/locking/lockdep.c:3113 [inline]
       validate_chain+0x1695/0x58f0 kernel/locking/lockdep.c:3729
       __lock_acquire+0x12fd/0x20d0 kernel/locking/lockdep.c:4955
       lock_acquire+0x197/0x480 kernel/locking/lockdep.c:5566
       down_write+0x93/0x180 kernel/locking/rwsem.c:1564
       inode_lock include/linux/fs.h:782 [inline]
       ext4_xattr_inode_iget+0x42a/0x5c0 fs/ext4/xattr.c:425
       ext4_xattr_inode_get+0x138/0x410 fs/ext4/xattr.c:485
       ext4_xattr_move_to_block fs/ext4/xattr.c:2580 [inline]
       ext4_xattr_make_inode_space fs/ext4/xattr.c:2682 [inline]
       ext4_expand_extra_isize_ea+0xe70/0x1bb0 fs/ext4/xattr.c:2774
       __ext4_expand_extra_isize+0x304/0x3f0 fs/ext4/inode.c:5898
       ext4_try_to_expand_extra_isize fs/ext4/inode.c:5941 [inline]
       __ext4_mark_inode_dirty+0x591/0x810 fs/ext4/inode.c:6018
       ext4_setattr+0x1400/0x19c0 fs/ext4/inode.c:5562
       notify_change+0xbb6/0xe60 fs/attr.c:435
       do_truncate+0x1de/0x2c0 fs/open.c:64
       handle_truncate fs/namei.c:2970 [inline]
       do_open fs/namei.c:3311 [inline]
       path_openat+0x29f3/0x3290 fs/namei.c:3425
       do_filp_open+0x20b/0x450 fs/namei.c:3452
       do_sys_openat2+0x124/0x460 fs/open.c:1207
       do_sys_open fs/open.c:1223 [inline]
       __do_sys_open fs/open.c:1231 [inline]
       __se_sys_open fs/open.c:1227 [inline]
       __x64_sys_open+0x221/0x270 fs/open.c:1227
       do_syscall_64+0x6d/0xa0 arch/x86/entry/common.c:62
       entry_SYSCALL_64_after_hwframe+0x61/0xcb

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ei->i_data_sem/3);
                               lock(&ea_inode->i_rwsem#7/1);
                               lock(&ei->i_data_sem/3);
  lock(&ea_inode->i_rwsem#7/1);

 *** DEADLOCK ***

5 locks held by syz-executor543/2794:
 #0: ffff888026fbc448 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x4a/0x2a0 fs/namespace.c:365
 #1: ffff8880215e3488 (&sb->s_type->i_mutex_key#7){++++}-{3:3}, at: inode_lock include/linux/fs.h:782 [inline]
 #1: ffff8880215e3488 (&sb->s_type->i_mutex_key#7){++++}-{3:3}, at: do_truncate+0x1cf/0x2c0 fs/open.c:62
 #2: ffff8880215e3310 (&ei->i_mmap_sem){++++}-{3:3}, at: ext4_setattr+0xec4/0x19c0 fs/ext4/inode.c:5519
 #3: ffff8880215e3278 (&ei->i_data_sem/3){++++}-{3:3}, at: ext4_setattr+0x136d/0x19c0 fs/ext4/inode.c:5559
 #4: ffff8880215e30c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_trylock_xattr fs/ext4/xattr.h:162 [inline]
 #4: ffff8880215e30c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_try_to_expand_extra_isize fs/ext4/inode.c:5938 [inline]
 #4: ffff8880215e30c8 (&ei->xattr_sem){++++}-{3:3}, at: __ext4_mark_inode_dirty+0x4fb/0x810 fs/ext4/inode.c:6018

stack backtrace:
CPU: 1 PID: 2794 Comm: syz-executor543 Not tainted 5.10.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x177/0x211 lib/dump_stack.c:118
 print_circular_bug+0x146/0x1b0 kernel/locking/lockdep.c:2002
 check_noncircular+0x2cc/0x390 kernel/locking/lockdep.c:2123
 check_prev_add kernel/locking/lockdep.c:2988 [inline]
 check_prevs_add kernel/locking/lockdep.c:3113 [inline]
 validate_chain+0x1695/0x58f0 kernel/locking/lockdep.c:3729
 __lock_acquire+0x12fd/0x20d0 kernel/locking/lockdep.c:4955
 lock_acquire+0x197/0x480 kernel/locking/lockdep.c:5566
 down_write+0x93/0x180 kernel/locking/rwsem.c:1564
 inode_lock include/linux/fs.h:782 [inline]
 ext4_xattr_inode_iget+0x42a/0x5c0 fs/ext4/xattr.c:425
 ext4_xattr_inode_get+0x138/0x410 fs/ext4/xattr.c:485
 ext4_xattr_move_to_block fs/ext4/xattr.c:2580 [inline]
 ext4_xattr_make_inode_space fs/ext4/xattr.c:2682 [inline]
 ext4_expand_extra_isize_ea+0xe70/0x1bb0 fs/ext4/xattr.c:2774
 __ext4_expand_extra_isize+0x304/0x3f0 fs/ext4/inode.c:5898
 ext4_try_to_expand_extra_isize fs/ext4/inode.c:5941 [inline]
 __ext4_mark_inode_dirty+0x591/0x810 fs/ext4/inode.c:6018
 ext4_setattr+0x1400/0x19c0 fs/ext4/inode.c:5562
 notify_change+0xbb6/0xe60 fs/attr.c:435
 do_truncate+0x1de/0x2c0 fs/open.c:64
 handle_truncate fs/namei.c:2970 [inline]
 do_open fs/namei.c:3311 [inline]
 path_openat+0x29f3/0x3290 fs/namei.c:3425
 do_filp_open+0x20b/0x450 fs/namei.c:3452
 do_sys_openat2+0x124/0x460 fs/open.c:1207
 do_sys_open fs/open.c:1223 [inline]
 __do_sys_open fs/open.c:1231 [inline]
 __se_sys_open fs/open.c:1227 [inline]
 __x64_sys_open+0x221/0x270 fs/open.c:1227
 do_syscall_64+0x6d/0xa0 arch/x86/entry/common.c:62
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f0cde4ea229
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 21 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd81d1c978 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0030656c69662f30 RCX: 00007f0cde4ea229
RDX: 0000000000000089 RSI: 00000000000a0a00 RDI: 00000000200001c0
RBP: 2f30656c69662f2e R08: 0000000000208000 R09: 0000000000208000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd81d1c9c0
R13: 00007ffd81d1ca00 R14: 0000000000080000 R15: 0000000000000003
EXT4-fs error (device loop0): ext4_expand_extra_isize_ea:2730: inode torvalds#13: comm syz-executor543: corrupted in-inode xattr

Signed-off-by: Wojciech Gładysz <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Theodore Ts'o <[email protected]>
kdave pushed a commit that referenced this pull request Sep 23, 2024
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
  #6  0x00005555557f00fb in iter_add_single_normal_entry (iter=0x7fffffffa900, al=0x7fffffffa8c0) at util/hist.c:1015
  #7  0x00005555557f09a7 in hist_entry_iter__add (iter=0x7fffffffa900, al=0x7fffffffa8c0, max_stack_depth=127, arg=0x7fffffffbce0)
      at util/hist.c:1260
  #8  0x00005555555ba7ce in process_sample_event (tool=0x7fffffffbce0, event=0x7ffff7c14128, sample=0x7fffffffaa90, evsel=0x555556039ad0,
      machine=0x5555560388e8) at builtin-report.c:334
  #9  0x00005555557b30c8 in evlist__deliver_sample (evlist=0x555556039010, tool=0x7fffffffbce0, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, evsel=0x555556039ad0, machine=0x5555560388e8) at util/session.c:1232
  #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]>
kdave pushed a commit that referenced this pull request Sep 23, 2024
There is a possibility to deadlock with an recursive
lock of the AP bus scan mutex ap_scan_bus_mutex:

  ... kernel: ============================================
  ... kernel: WARNING: possible recursive locking detected
  ... kernel: 5.14.0-496.el9.s390x #3 Not tainted
  ... kernel: --------------------------------------------
  ... kernel: kworker/12:1/130 is trying to acquire lock:
  ... kernel: 0000000358bc1510 (ap_scan_bus_mutex){+.+.}-{3:3}, at: ap_bus_force_rescan+0x92/0x108
  ... kernel:
	      but task is already holding lock:
  ... kernel: 0000000358bc1510 (ap_scan_bus_mutex){+.+.}-{3:3}, at: ap_scan_bus_wq_callback+0x28/0x60
  ... kernel:
	      other info that might help us debug this:
  ... kernel:  Possible unsafe locking scenario:
  ... kernel:        CPU0
  ... kernel:        ----
  ... kernel:   lock(ap_scan_bus_mutex);
  ... kernel:   lock(ap_scan_bus_mutex);
  ... kernel:
	      *** DEADLOCK ***

Here is how the callstack looks like:

  ... [<00000003576fe9ce>] process_one_work+0x2a6/0x748
  ... [<0000000358150c00>] ap_scan_bus_wq_callback+0x40/0x60   <- mutex locked
  ... [<00000003581506e2>] ap_scan_bus+0x5a/0x3b0
  ... [<000000035815037c>] ap_scan_adapter+0x5b4/0x8c0
  ... [<000000035814fa34>] ap_scan_domains+0x2d4/0x668
  ... [<0000000357d989b4>] device_add+0x4a4/0x6b8
  ... [<0000000357d9bb54>] bus_probe_device+0xb4/0xc8
  ... [<0000000357d9daa8>] __device_attach+0x120/0x1b0
  ... [<0000000357d9a632>] bus_for_each_drv+0x8a/0xd0
  ... [<0000000357d9d548>] __device_attach_driver+0xc0/0x140
  ... [<0000000357d9d3d8>] driver_probe_device+0x40/0xf0
  ... [<0000000357d9cec2>] really_probe+0xd2/0x460
  ... [<000000035814d7b0>] ap_device_probe+0x150/0x208
  ... [<000003ff802a5c46>] zcrypt_cex4_queue_probe+0xb6/0x1c0 [zcrypt_cex4]
  ... [<000003ff7fb2d36e>] zcrypt_queue_register+0xe6/0x1b0 [zcrypt]
  ... [<000003ff7fb2c8ac>] zcrypt_rng_device_add+0x94/0xd8 [zcrypt]
  ... [<0000000357d7bc52>] hwrng_register+0x212/0x228
  ... [<0000000357d7b8c2>] add_early_randomness+0x102/0x110
  ... [<000003ff7fb29c94>] zcrypt_rng_data_read+0x94/0xb8 [zcrypt]
  ... [<0000000358150aca>] ap_bus_force_rescan+0x92/0x108
  ... [<0000000358177572>] mutex_lock_interruptible_nested+0x32/0x40  <- lock again

Note this only happens when the very first random data providing
crypto card appears via hot plug in the system AND is in disabled
state ("deconfig"). Then the initial pull of random data fails and
a re-scan of the AP bus is triggered while already in the middle
of an AP bus scan caused by the appearing new hardware.

The fix is relatively simple once the scenario us understood:
The AP bus force rescan function will immediately return if there
is currently an AP bus scan running with the very same thread id.

Fixes: eacf5b3 ("s390/ap: introduce mutex to lock the AP bus scan")
Signed-off-by: Harald Freudenberger <[email protected]>
Signed-off-by: Heiko Carstens <[email protected]>
Signed-off-by: Vasily Gorbik <[email protected]>
kdave pushed a commit that referenced this pull request Sep 23, 2024
…ptions

Patch series "mm: split PTE/PMD PT table Kconfig cleanups+clarifications".

This series is a follow up to the fixes:
	"[PATCH v1 0/2] mm/hugetlb: fix hugetlb vs. core-mm PT locking"

When working on the fixes, I wondered why 8xx is fine (-> never uses split
PT locks) and how PT locking even works properly with PMD page table
sharing (-> always requires split PMD PT locks).

Let's improve the split PT lock detection, make hugetlb properly depend on
it and make 8xx bail out if it would ever get enabled by accident.

As an alternative to patch #3 we could extend the Kconfig
SPLIT_PTE_PTLOCKS option from patch #2 -- but enforcing it closer to the
code that actually implements it feels a bit nicer for documentation
purposes, and there is no need to actually disable it because it should
always be disabled (!SMP).

Did a bunch of cross-compilations to make sure that split PTE/PMD PT locks
are still getting used where we would expect them.

[1] https://lkml.kernel.org/r/[email protected]


This patch (of 3):

Let's clean that up a bit and prepare for depending on
CONFIG_SPLIT_PMD_PTLOCKS in other Kconfig options.

More cleanups would be reasonable (like the arch-specific "depends on" for
CONFIG_SPLIT_PTE_PTLOCKS), but we'll leave that for another day.

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: David Hildenbrand <[email protected]>
Acked-by: Mike Rapoport (Microsoft) <[email protected]>
Reviewed-by: Russell King (Oracle) <[email protected]>
Reviewed-by: Qi Zheng <[email protected]>
Cc: Alexander Viro <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Boris Ostrovsky <[email protected]>
Cc: Christian Brauner <[email protected]>
Cc: Christophe Leroy <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Juergen Gross <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Muchun Song <[email protected]>
Cc: "Naveen N. Rao" <[email protected]>
Cc: Nicholas Piggin <[email protected]>
Cc: Oscar Salvador <[email protected]>
Cc: Peter Xu <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
kdave pushed a commit that referenced this pull request Sep 23, 2024
commit 823430c ("memory tier: consolidate the initialization of
memory tiers") introduces a locking change that use guard(mutex) to
instead of mutex_lock/unlock() for memory_tier_lock.  It unexpectedly
expanded the locked region to include the hotplug_memory_notifier(), as a
result, it triggers an locking dependency detected of ABBA deadlock. 
Exclude hotplug_memory_notifier() from the locked region to fixing it.

The deadlock scenario is that when a memory online event occurs, the
execution of memory notifier will access the read lock of the
memory_chain.rwsem, then the reigistration of the memory notifier in
memory_tier_init() acquires the write lock of the memory_chain.rwsem while
holding memory_tier_lock.  Then the memory online event continues to
invoke the memory hotplug callback registered by memory_tier_init(). 
Since this callback tries to acquire the memory_tier_lock, a deadlock
occurs.

In fact, this deadlock can't happen because memory_tier_init() always
executes before memory online events happen due to the subsys_initcall()
has an higher priority than module_init().

[  133.491106] WARNING: possible circular locking dependency detected
[  133.493656] 6.11.0-rc2+ torvalds#146 Tainted: G           O     N
[  133.504290] ------------------------------------------------------
[  133.515194] (udev-worker)/1133 is trying to acquire lock:
[  133.525715] ffffffff87044e28 (memory_tier_lock){+.+.}-{3:3}, at: memtier_hotplug_callback+0x383/0x4b0
[  133.536449]
[  133.536449] but task is already holding lock:
[  133.549847] ffffffff875d3310 ((memory_chain).rwsem){++++}-{3:3}, at: blocking_notifier_call_chain+0x60/0xb0
[  133.556781]
[  133.556781] which lock already depends on the new lock.
[  133.556781]
[  133.569957]
[  133.569957] the existing dependency chain (in reverse order) is:
[  133.577618]
[  133.577618] -> #1 ((memory_chain).rwsem){++++}-{3:3}:
[  133.584997]        down_write+0x97/0x210
[  133.588647]        blocking_notifier_chain_register+0x71/0xd0
[  133.592537]        register_memory_notifier+0x26/0x30
[  133.596314]        memory_tier_init+0x187/0x300
[  133.599864]        do_one_initcall+0x117/0x5d0
[  133.603399]        kernel_init_freeable+0xab0/0xeb0
[  133.606986]        kernel_init+0x28/0x2f0
[  133.610312]        ret_from_fork+0x59/0x90
[  133.613652]        ret_from_fork_asm+0x1a/0x30
[  133.617012]
[  133.617012] -> #0 (memory_tier_lock){+.+.}-{3:3}:
[  133.623390]        __lock_acquire+0x2efd/0x5c60
[  133.626730]        lock_acquire+0x1ce/0x580
[  133.629757]        __mutex_lock+0x15c/0x1490
[  133.632731]        mutex_lock_nested+0x1f/0x30
[  133.635717]        memtier_hotplug_callback+0x383/0x4b0
[  133.638748]        notifier_call_chain+0xbf/0x370
[  133.641647]        blocking_notifier_call_chain+0x76/0xb0
[  133.644636]        memory_notify+0x2e/0x40
[  133.647427]        online_pages+0x597/0x720
[  133.650246]        memory_subsys_online+0x4f6/0x7f0
[  133.653107]        device_online+0x141/0x1d0
[  133.655831]        online_memory_block+0x4d/0x60
[  133.658616]        walk_memory_blocks+0xc0/0x120
[  133.661419]        add_memory_resource+0x51d/0x6c0
[  133.664202]        add_memory_driver_managed+0xf5/0x180
[  133.667060]        dev_dax_kmem_probe+0x7f7/0xb40 [kmem]
[  133.669949]        dax_bus_probe+0x147/0x230
[  133.672687]        really_probe+0x27f/0xac0
[  133.675463]        __driver_probe_device+0x1f3/0x460
[  133.678493]        driver_probe_device+0x56/0x1b0
[  133.681366]        __driver_attach+0x277/0x570
[  133.684149]        bus_for_each_dev+0x145/0x1e0
[  133.686937]        driver_attach+0x49/0x60
[  133.689673]        bus_add_driver+0x2f3/0x6b0
[  133.692421]        driver_register+0x170/0x4b0
[  133.695118]        __dax_driver_register+0x141/0x1b0
[  133.697910]        dax_kmem_init+0x54/0xff0 [kmem]
[  133.700794]        do_one_initcall+0x117/0x5d0
[  133.703455]        do_init_module+0x277/0x750
[  133.706054]        load_module+0x5d1d/0x74f0
[  133.708602]        init_module_from_file+0x12c/0x1a0
[  133.711234]        idempotent_init_module+0x3f1/0x690
[  133.713937]        __x64_sys_finit_module+0x10e/0x1a0
[  133.716492]        x64_sys_call+0x184d/0x20d0
[  133.719053]        do_syscall_64+0x6d/0x140
[  133.721537]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
[  133.724239]
[  133.724239] other info that might help us debug this:
[  133.724239]
[  133.730832]  Possible unsafe locking scenario:
[  133.730832]
[  133.735298]        CPU0                    CPU1
[  133.737759]        ----                    ----
[  133.740165]   rlock((memory_chain).rwsem);
[  133.742623]                                lock(memory_tier_lock);
[  133.745357]                                lock((memory_chain).rwsem);
[  133.748141]   lock(memory_tier_lock);
[  133.750489]
[  133.750489]  *** DEADLOCK ***
[  133.750489]
[  133.756742] 6 locks held by (udev-worker)/1133:
[  133.759179]  #0: ffff888207be6158 (&dev->mutex){....}-{3:3}, at: __driver_attach+0x26c/0x570
[  133.762299]  #1: ffffffff875b5868 (device_hotplug_lock){+.+.}-{3:3}, at: lock_device_hotplug+0x20/0x30
[  133.765565]  #2: ffff88820cf6a108 (&dev->mutex){....}-{3:3}, at: device_online+0x2f/0x1d0
[  133.768978]  #3: ffffffff86d08ff0 (cpu_hotplug_lock){++++}-{0:0}, at: mem_hotplug_begin+0x17/0x30
[  133.772312]  #4: ffffffff8702dfb0 (mem_hotplug_lock){++++}-{0:0}, at: mem_hotplug_begin+0x23/0x30
[  133.775544]  #5: ffffffff875d3310 ((memory_chain).rwsem){++++}-{3:3}, at: blocking_notifier_call_chain+0x60/0xb0
[  133.779113]
[  133.779113] stack backtrace:
[  133.783728] CPU: 5 UID: 0 PID: 1133 Comm: (udev-worker) Tainted: G           O     N 6.11.0-rc2+ torvalds#146
[  133.787220] Tainted: [O]=OOT_MODULE, [N]=TEST
[  133.789948] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
[  133.793291] Call Trace:
[  133.795826]  <TASK>
[  133.798284]  dump_stack_lvl+0xea/0x150
[  133.801025]  dump_stack+0x19/0x20
[  133.803609]  print_circular_bug+0x477/0x740
[  133.806341]  check_noncircular+0x2f4/0x3e0
[  133.809056]  ? __pfx_check_noncircular+0x10/0x10
[  133.811866]  ? __pfx_lockdep_lock+0x10/0x10
[  133.814670]  ? __sanitizer_cov_trace_const_cmp8+0x1c/0x30
[  133.817610]  __lock_acquire+0x2efd/0x5c60
[  133.820339]  ? __pfx___lock_acquire+0x10/0x10
[  133.823128]  ? __dax_driver_register+0x141/0x1b0
[  133.825926]  ? do_one_initcall+0x117/0x5d0
[  133.828648]  lock_acquire+0x1ce/0x580
[  133.831349]  ? memtier_hotplug_callback+0x383/0x4b0
[  133.834293]  ? __pfx_lock_acquire+0x10/0x10
[  133.837134]  __mutex_lock+0x15c/0x1490
[  133.839829]  ? memtier_hotplug_callback+0x383/0x4b0
[  133.842753]  ? memtier_hotplug_callback+0x383/0x4b0
[  133.845602]  ? __this_cpu_preempt_check+0x21/0x30
[  133.848438]  ? __pfx___mutex_lock+0x10/0x10
[  133.851200]  ? __pfx_lock_acquire+0x10/0x10
[  133.853935]  ? global_dirty_limits+0xc0/0x160
[  133.856699]  ? __sanitizer_cov_trace_switch+0x58/0xa0
[  133.859564]  mutex_lock_nested+0x1f/0x30
[  133.862251]  ? mutex_lock_nested+0x1f/0x30
[  133.864964]  memtier_hotplug_callback+0x383/0x4b0
[  133.867752]  notifier_call_chain+0xbf/0x370
[  133.870550]  ? writeback_set_ratelimit+0xe8/0x160
[  133.873372]  blocking_notifier_call_chain+0x76/0xb0
[  133.876311]  memory_notify+0x2e/0x40
[  133.879013]  online_pages+0x597/0x720
[  133.881686]  ? irqentry_exit+0x3e/0xa0
[  133.884397]  ? __pfx_online_pages+0x10/0x10
[  133.887244]  ? __sanitizer_cov_trace_const_cmp8+0x1c/0x30
[  133.890299]  ? mhp_init_memmap_on_memory+0x7a/0x1c0
[  133.893203]  memory_subsys_online+0x4f6/0x7f0
[  133.896099]  ? __pfx_memory_subsys_online+0x10/0x10
[  133.899039]  ? xa_load+0x16d/0x2e0
[  133.901667]  ? __pfx_xa_load+0x10/0x10
[  133.904366]  ? __pfx_memory_subsys_online+0x10/0x10
[  133.907218]  device_online+0x141/0x1d0
[  133.909845]  online_memory_block+0x4d/0x60
[  133.912494]  walk_memory_blocks+0xc0/0x120
[  133.915104]  ? __pfx_online_memory_block+0x10/0x10
[  133.917776]  add_memory_resource+0x51d/0x6c0
[  133.920404]  ? __pfx_add_memory_resource+0x10/0x10
[  133.923104]  ? _raw_write_unlock+0x31/0x60
[  133.925781]  ? register_memory_resource+0x119/0x180
[  133.928450]  add_memory_driver_managed+0xf5/0x180
[  133.931036]  dev_dax_kmem_probe+0x7f7/0xb40 [kmem]
[  133.933665]  ? __pfx_dev_dax_kmem_probe+0x10/0x10 [kmem]
[  133.936332]  ? __pfx___up_read+0x10/0x10
[  133.938878]  dax_bus_probe+0x147/0x230
[  133.941332]  ? __pfx_dax_bus_probe+0x10/0x10
[  133.943954]  really_probe+0x27f/0xac0
[  133.946387]  ? __sanitizer_cov_trace_const_cmp1+0x1e/0x30
[  133.949106]  __driver_probe_device+0x1f3/0x460
[  133.951704]  ? parse_option_str+0x149/0x190
[  133.954241]  driver_probe_device+0x56/0x1b0
[  133.956749]  __driver_attach+0x277/0x570
[  133.959228]  ? __pfx___driver_attach+0x10/0x10
[  133.961776]  bus_for_each_dev+0x145/0x1e0
[  133.964367]  ? __pfx_bus_for_each_dev+0x10/0x10
[  133.967019]  ? __kasan_check_read+0x15/0x20
[  133.969543]  ? _raw_spin_unlock+0x31/0x60
[  133.972132]  driver_attach+0x49/0x60
[  133.974536]  bus_add_driver+0x2f3/0x6b0
[  133.977044]  driver_register+0x170/0x4b0
[  133.979480]  __dax_driver_register+0x141/0x1b0
[  133.982126]  ? __pfx_dax_kmem_init+0x10/0x10 [kmem]
[  133.984724]  dax_kmem_init+0x54/0xff0 [kmem]
[  133.987284]  ? __pfx_dax_kmem_init+0x10/0x10 [kmem]
[  133.989965]  do_one_initcall+0x117/0x5d0
[  133.992506]  ? __pfx_do_one_initcall+0x10/0x10
[  133.995185]  ? __kasan_kmalloc+0x88/0xa0
[  133.997748]  ? kasan_poison+0x3e/0x60
[  134.000288]  ? kasan_unpoison+0x2c/0x60
[  134.002762]  ? kasan_poison+0x3e/0x60
[  134.005202]  ? __asan_register_globals+0x62/0x80
[  134.007753]  ? __pfx_dax_kmem_init+0x10/0x10 [kmem]
[  134.010439]  do_init_module+0x277/0x750
[  134.012953]  load_module+0x5d1d/0x74f0
[  134.015406]  ? __pfx_load_module+0x10/0x10
[  134.017887]  ? __pfx_ima_post_read_file+0x10/0x10
[  134.020470]  ? __sanitizer_cov_trace_const_cmp8+0x1c/0x30
[  134.023127]  ? __sanitizer_cov_trace_const_cmp4+0x1a/0x20
[  134.025767]  ? security_kernel_post_read_file+0xa2/0xd0
[  134.028429]  ? __sanitizer_cov_trace_const_cmp4+0x1a/0x20
[  134.031162]  ? kernel_read_file+0x503/0x820
[  134.033645]  ? __pfx_kernel_read_file+0x10/0x10
[  134.036232]  ? __pfx___lock_acquire+0x10/0x10
[  134.038766]  init_module_from_file+0x12c/0x1a0
[  134.041291]  ? init_module_from_file+0x12c/0x1a0
[  134.043936]  ? __pfx_init_module_from_file+0x10/0x10
[  134.046516]  ? __this_cpu_preempt_check+0x21/0x30
[  134.049091]  ? __kasan_check_read+0x15/0x20
[  134.051551]  ? do_raw_spin_unlock+0x60/0x210
[  134.054077]  idempotent_init_module+0x3f1/0x690
[  134.056643]  ? __pfx_idempotent_init_module+0x10/0x10
[  134.059318]  ? __sanitizer_cov_trace_const_cmp4+0x1a/0x20
[  134.061995]  ? __fget_light+0x17d/0x210
[  134.064428]  __x64_sys_finit_module+0x10e/0x1a0
[  134.066976]  x64_sys_call+0x184d/0x20d0
[  134.069405]  do_syscall_64+0x6d/0x140
[  134.071926]  entry_SYSCALL_64_after_hwframe+0x76/0x7e

[[email protected]: add mutex_lock/unlock() pair back]
  Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Fixes: 823430c ("memory tier: consolidate the initialization of memory tiers")
Signed-off-by: Yanfei Xu <[email protected]>
Reviewed-by: "Huang, Ying" <[email protected]>
Cc: Ho-Ren (Jack) Chuang <[email protected]>
Cc: Jonathan Cameron <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
kdave pushed a commit that referenced this pull request Sep 23, 2024
llvm change [1] made a change such that __sync_fetch_and_{and,or,xor}()
will generate atomic_fetch_*() insns even if the return value is not used.
This is a deliberate choice to make sure barrier semantics are preserved
from source code to asm insn.

But the change in [1] caused arena_atomics selftest failure.

  test_arena_atomics:PASS:arena atomics skeleton open 0 nsec
  libbpf: prog 'and': BPF program load failed: Permission denied
  libbpf: prog 'and': -- BEGIN PROG LOAD LOG --
  arg#0 reference type('UNKNOWN ') size cannot be determined: -22
  0: R1=ctx() R10=fp0
  ; if (pid != (bpf_get_current_pid_tgid() >> 32)) @ arena_atomics.c:87
  0: (18) r1 = 0xffffc90000064000       ; R1_w=map_value(map=arena_at.bss,ks=4,vs=4)
  2: (61) r6 = *(u32 *)(r1 +0)          ; R1_w=map_value(map=arena_at.bss,ks=4,vs=4) R6_w=scalar(smin=0,smax=umax=0xffffffff,v
ar_off=(0x0; 0xffffffff))
  3: (85) call bpf_get_current_pid_tgid#14      ; R0_w=scalar()
  4: (77) r0 >>= 32                     ; R0_w=scalar(smin=0,smax=umax=0xffffffff,var_off=(0x0; 0xffffffff))
  5: (5d) if r0 != r6 goto pc+11        ; R0_w=scalar(smin=0,smax=umax=0xffffffff,var_off=(0x0; 0xffffffff)) R6_w=scalar(smin=0,smax=umax=0xffffffff,var_off=(0x0; 0x)
  ; __sync_fetch_and_and(&and64_value, 0x011ull << 32); @ arena_atomics.c:91
  6: (18) r1 = 0x100000000060           ; R1_w=scalar()
  8: (bf) r1 = addr_space_cast(r1, 0, 1)        ; R1_w=arena
  9: (18) r2 = 0x1100000000             ; R2_w=0x1100000000
  11: (db) r2 = atomic64_fetch_and((u64 *)(r1 +0), r2)
  BPF_ATOMIC stores into R1 arena is not allowed
  processed 9 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0
  -- END PROG LOAD LOG --
  libbpf: prog 'and': failed to load: -13
  libbpf: failed to load object 'arena_atomics'
  libbpf: failed to load BPF skeleton 'arena_atomics': -13
  test_arena_atomics:FAIL:arena atomics skeleton load unexpected error: -13 (errno 13)
  #3       arena_atomics:FAIL

The reason of the failure is due to [2] where atomic{64,}_fetch_{and,or,xor}() are not
allowed by arena addresses.

Version 2 of the patch fixed the issue by using inline asm ([3]). But further discussion
suggested to find a way from source to generate locked insn which is more user
friendly. So in not-merged llvm patch ([4]), if relax memory ordering is used and
the return value is not used, locked insn could be generated.

So with llvm patch [4] to compile the bpf selftest, the following code
  __c11_atomic_fetch_and(&and64_value, 0x011ull << 32, memory_order_relaxed);
is able to generate locked insn, hence fixing the selftest failure.

  [1] llvm/llvm-project#106494
  [2] d503a04 ("bpf: Add support for certain atomics in bpf_arena to x86 JIT")
  [3] https://lore.kernel.org/bpf/[email protected]/
  [4] llvm/llvm-project#107343

Signed-off-by: Yonghong Song <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>
kdave pushed a commit that referenced this pull request Sep 25, 2024
When ib_cache_update return an error, we exit ib_cache_setup_one
instantly with no proper cleanup, even though before this we had
already successfully done gid_table_setup_one, that results in
the kernel WARN below.

Do proper cleanup using gid_table_cleanup_one before returning
the err in order to fix the issue.

WARNING: CPU: 4 PID: 922 at drivers/infiniband/core/cache.c:806 gid_table_release_one+0x181/0x1a0
Modules linked in:
CPU: 4 UID: 0 PID: 922 Comm: c_repro Not tainted 6.11.0-rc1+ #3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:gid_table_release_one+0x181/0x1a0
Code: 44 8b 38 75 0c e8 2f cb 34 ff 4d 8b b5 28 05 00 00 e8 23 cb 34 ff 44 89 f9 89 da 4c 89 f6 48 c7 c7 d0 58 14 83 e8 4f de 21 ff <0f> 0b 4c 8b 75 30 e9 54 ff ff ff 48 8    3 c4 10 5b 5d 41 5c 41 5d 41
RSP: 0018:ffffc90002b835b0 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff811c8527
RDX: 0000000000000000 RSI: ffffffff811c8534 RDI: 0000000000000001
RBP: ffff8881011b3d00 R08: ffff88810b3abe00 R09: 205d303839303631
R10: 666572207972746e R11: 72746e6520444947 R12: 0000000000000001
R13: ffff888106390000 R14: ffff8881011f2110 R15: 0000000000000001
FS:  00007fecc3b70800(0000) GS:ffff88813bd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000340 CR3: 000000010435a001 CR4: 00000000003706b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ? show_regs+0x94/0xa0
 ? __warn+0x9e/0x1c0
 ? gid_table_release_one+0x181/0x1a0
 ? report_bug+0x1f9/0x340
 ? gid_table_release_one+0x181/0x1a0
 ? handle_bug+0xa2/0x110
 ? exc_invalid_op+0x31/0xa0
 ? asm_exc_invalid_op+0x16/0x20
 ? __warn_printk+0xc7/0x180
 ? __warn_printk+0xd4/0x180
 ? gid_table_release_one+0x181/0x1a0
 ib_device_release+0x71/0xe0
 ? __pfx_ib_device_release+0x10/0x10
 device_release+0x44/0xd0
 kobject_put+0x135/0x3d0
 put_device+0x20/0x30
 rxe_net_add+0x7d/0xa0
 rxe_newlink+0xd7/0x190
 nldev_newlink+0x1b0/0x2a0
 ? __pfx_nldev_newlink+0x10/0x10
 rdma_nl_rcv_msg+0x1ad/0x2e0
 rdma_nl_rcv_skb.constprop.0+0x176/0x210
 netlink_unicast+0x2de/0x400
 netlink_sendmsg+0x306/0x660
 __sock_sendmsg+0x110/0x120
 ____sys_sendmsg+0x30e/0x390
 ___sys_sendmsg+0x9b/0xf0
 ? kstrtouint+0x6e/0xa0
 ? kstrtouint_from_user+0x7c/0xb0
 ? get_pid_task+0xb0/0xd0
 ? proc_fail_nth_write+0x5b/0x140
 ? __fget_light+0x9a/0x200
 ? preempt_count_add+0x47/0xa0
 __sys_sendmsg+0x61/0xd0
 do_syscall_64+0x50/0x110
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Fixes: 1901b91 ("IB/core: Fix potential NULL pointer dereference in pkey cache")
Signed-off-by: Patrisious Haddad <[email protected]>
Reviewed-by: Maher Sanalla <[email protected]>
Link: https://patch.msgid.link/79137687d829899b0b1c9835fcb4b258004c439a.1725273354.git.leon@kernel.org
Signed-off-by: Leon Romanovsky <[email protected]>
kdave pushed a commit that referenced this pull request Sep 26, 2024
…git/netfilter/nf

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

v2: with kdoc fixes per Paolo Abeni.

The following patchset contains Netfilter fixes for net:

Patch #1 and #2 handle an esoteric scenario: Given two tasks sending UDP
packets to one another, two packets of the same flow in each direction
handled by different CPUs that result in two conntrack objects in NEW
state, where reply packet loses race. Then, patch #3 adds a testcase for
this scenario. Series from Florian Westphal.

1) NAT engine can falsely detect a port collision if it happens to pick
   up a reply packet as NEW rather than ESTABLISHED. Add extra code to
   detect this and suppress port reallocation in this case.

2) To complete the clash resolution in the reply direction, extend conntrack
   logic to detect clashing conntrack in the reply direction to existing entry.

3) Adds a test case.

Then, an assorted list of fixes follow:

4) Add a selftest for tproxy, from Antonio Ojea.

5) Guard ctnetlink_*_size() functions under
   #if defined(CONFIG_NETFILTER_NETLINK_GLUE_CT) || defined(CONFIG_NF_CONNTRACK_EVENTS)
   From Andy Shevchenko.

6) Use -m socket --transparent in iptables tproxy documentation.
   From XIE Zhibang.

7) Call kfree_rcu() when releasing flowtable hooks to address race with
   netlink dump path, from Phil Sutter.

8) Fix compilation warning in nf_reject with CONFIG_BRIDGE_NETFILTER=n.
   From Simon Horman.

9) Guard ctnetlink_label_size() under CONFIG_NF_CONNTRACK_EVENTS which
   is its only user, to address a compilation warning. From Simon Horman.

10) Use rcu-protected list iteration over basechain hooks from netlink
    dump path.

11) Fix memcg for nf_tables, use GFP_KERNEL_ACCOUNT is not complete.

12) Remove old nfqueue conntrack clash resolution. Instead trying to
    use same destination address consistently which requires double DNAT,
    use the existing clash resolution which allows clashing packets
    go through with different destination. Antonio Ojea originally
    reported an issue from the postrouting chain, I proposed a fix:
    https://lore.kernel.org/netfilter-devel/ZuwSwAqKgCB2a51-@calendula/T/
    which he reported it did not work for him.

13) Adds a selftest for patch 12.

14) Fixes ipvs.sh selftest.

netfilter pull request 24-09-26

* tag 'nf-24-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
  selftests: netfilter: Avoid hanging ipvs.sh
  kselftest: add test for nfqueue induced conntrack race
  netfilter: nfnetlink_queue: remove old clash resolution logic
  netfilter: nf_tables: missing objects with no memcg accounting
  netfilter: nf_tables: use rcu chain hook list iterator from netlink dump path
  netfilter: ctnetlink: compile ctnetlink_label_size with CONFIG_NF_CONNTRACK_EVENTS
  netfilter: nf_reject: Fix build warning when CONFIG_BRIDGE_NETFILTER=n
  netfilter: nf_tables: Keep deleted flowtable hooks until after RCU
  docs: tproxy: ignore non-transparent sockets in iptables
  netfilter: ctnetlink: Guard possible unused functions
  selftests: netfilter: nft_tproxy.sh: add tcp tests
  selftests: netfilter: add reverse-clash resolution test case
  netfilter: conntrack: add clash resolution for reverse collisions
  netfilter: nf_nat: don't try nat source port reallocation for reverse dir clash
====================

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Paolo Abeni <[email protected]>
kdave pushed a commit that referenced this pull request Sep 30, 2024
The following calculation used in coalesced_mmio_has_room() to check
whether the ring buffer is full is wrong and results in premature exits if
the start of the valid entries is in the first half of the ring buffer.

  avail = (ring->first - last - 1) % KVM_COALESCED_MMIO_MAX;
  if (avail == 0)
	  /* full */

Because negative values are handled using two's complement, and KVM
computes the result as an unsigned value, the above will get a false
positive if "first < last" and the ring is half-full.

The above might have worked as expected in python for example:
  >>> (-86) % 170
  84

However it doesn't work the same way in C.

  printf("avail: %d\n", (-86) % 170);
  printf("avail: %u\n", (-86) % 170);
  printf("avail: %u\n", (-86u) % 170u);

Using gcc-11 these print:

  avail: -86
  avail: 4294967210
  avail: 0

For illustration purposes, given a 4-bit integer and a ring size of 0xA
(unsigned), 0xA == 0x1010 == -6, and thus (-6u % 0xA) == 0.

Fix the calculation and allow all but one entries in the buffer to be
used as originally intended.

Note, KVM's behavior is self-healing to some extent, as KVM will allow the
entire buffer to be used if ring->first is beyond the halfway point.  In
other words, in the unlikely scenario that a use case benefits from being
able to coalesce more than 86 entries at once, KVM will still provide such
behavior, sometimes.

Note #2, the % operator in C is not the modulo operator but the remainder
operator. Modulo and remainder operators differ with respect to negative
values.  But, the relevant values in KVM are all unsigned, so it's a moot
point in this case anyway.

Note #3, this is almost a pure revert of the buggy commit, plus a
READ_ONCE() to provide additional safety.  Thue buggy commit justified the
change with "it paves the way for making this function lockless", but it's
not at all clear what was intended, nor is there any evidence that the
buggy code was somehow safer.  (a) the fields in question were already
accessed locklessly, from the perspective that they could be modified by
userspace at any time, and (b) the lock guarding the ring itself was
changed, but never dropped, i.e. whatever lockless scheme (SRCU?) was
planned never landed.

Fixes: 105f8d4 ("KVM: Calculate available entries in coalesced mmio ring")
Signed-off-by: Ilias Stamatis <[email protected]>
Reviewed-by: Paul Durrant <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[sean: rework changelog to clarify behavior, call out weirdness of buggy commit]
Signed-off-by: Sean Christopherson <[email protected]>
kdave pushed a commit that referenced this pull request Sep 30, 2024
Use a dedicated mutex to guard kvm_usage_count to fix a potential deadlock
on x86 due to a chain of locks and SRCU synchronizations.  Translating the
below lockdep splat, CPU1 #6 will wait on CPU0 #1, CPU0 #8 will wait on
CPU2 #3, and CPU2 #7 will wait on CPU1 #4 (if there's a writer, due to the
fairness of r/w semaphores).

    CPU0                     CPU1                     CPU2
1   lock(&kvm->slots_lock);
2                                                     lock(&vcpu->mutex);
3                                                     lock(&kvm->srcu);
4                            lock(cpu_hotplug_lock);
5                            lock(kvm_lock);
6                            lock(&kvm->slots_lock);
7                                                     lock(cpu_hotplug_lock);
8   sync(&kvm->srcu);

Note, there are likely more potential deadlocks in KVM x86, e.g. the same
pattern of taking cpu_hotplug_lock outside of kvm_lock likely exists with
__kvmclock_cpufreq_notifier():

  cpuhp_cpufreq_online()
  |
  -> cpufreq_online()
     |
     -> cpufreq_gov_performance_limits()
        |
        -> __cpufreq_driver_target()
           |
           -> __target_index()
              |
              -> cpufreq_freq_transition_begin()
                 |
                 -> cpufreq_notify_transition()
                    |
                    -> ... __kvmclock_cpufreq_notifier()

But, actually triggering such deadlocks is beyond rare due to the
combination of dependencies and timings involved.  E.g. the cpufreq
notifier is only used on older CPUs without a constant TSC, mucking with
the NX hugepage mitigation while VMs are running is very uncommon, and
doing so while also onlining/offlining a CPU (necessary to generate
contention on cpu_hotplug_lock) would be even more unusual.

The most robust solution to the general cpu_hotplug_lock issue is likely
to switch vm_list to be an RCU-protected list, e.g. so that x86's cpufreq
notifier doesn't to take kvm_lock.  For now, settle for fixing the most
blatant deadlock, as switching to an RCU-protected list is a much more
involved change, but add a comment in locking.rst to call out that care
needs to be taken when walking holding kvm_lock and walking vm_list.

  ======================================================
  WARNING: possible circular locking dependency detected
  6.10.0-smp--c257535a0c9d-pip torvalds#330 Tainted: G S         O
  ------------------------------------------------------
  tee/35048 is trying to acquire lock:
  ff6a80eced71e0a8 (&kvm->slots_lock){+.+.}-{3:3}, at: set_nx_huge_pages+0x179/0x1e0 [kvm]

  but task is already holding lock:
  ffffffffc07abb08 (kvm_lock){+.+.}-{3:3}, at: set_nx_huge_pages+0x14a/0x1e0 [kvm]

  which lock already depends on the new lock.

   the existing dependency chain (in reverse order) is:

  -> #3 (kvm_lock){+.+.}-{3:3}:
         __mutex_lock+0x6a/0xb40
         mutex_lock_nested+0x1f/0x30
         kvm_dev_ioctl+0x4fb/0xe50 [kvm]
         __se_sys_ioctl+0x7b/0xd0
         __x64_sys_ioctl+0x21/0x30
         x64_sys_call+0x15d0/0x2e60
         do_syscall_64+0x83/0x160
         entry_SYSCALL_64_after_hwframe+0x76/0x7e

  -> #2 (cpu_hotplug_lock){++++}-{0:0}:
         cpus_read_lock+0x2e/0xb0
         static_key_slow_inc+0x16/0x30
         kvm_lapic_set_base+0x6a/0x1c0 [kvm]
         kvm_set_apic_base+0x8f/0xe0 [kvm]
         kvm_set_msr_common+0x9ae/0xf80 [kvm]
         vmx_set_msr+0xa54/0xbe0 [kvm_intel]
         __kvm_set_msr+0xb6/0x1a0 [kvm]
         kvm_arch_vcpu_ioctl+0xeca/0x10c0 [kvm]
         kvm_vcpu_ioctl+0x485/0x5b0 [kvm]
         __se_sys_ioctl+0x7b/0xd0
         __x64_sys_ioctl+0x21/0x30
         x64_sys_call+0x15d0/0x2e60
         do_syscall_64+0x83/0x160
         entry_SYSCALL_64_after_hwframe+0x76/0x7e

  -> #1 (&kvm->srcu){.+.+}-{0:0}:
         __synchronize_srcu+0x44/0x1a0
         synchronize_srcu_expedited+0x21/0x30
         kvm_swap_active_memslots+0x110/0x1c0 [kvm]
         kvm_set_memslot+0x360/0x620 [kvm]
         __kvm_set_memory_region+0x27b/0x300 [kvm]
         kvm_vm_ioctl_set_memory_region+0x43/0x60 [kvm]
         kvm_vm_ioctl+0x295/0x650 [kvm]
         __se_sys_ioctl+0x7b/0xd0
         __x64_sys_ioctl+0x21/0x30
         x64_sys_call+0x15d0/0x2e60
         do_syscall_64+0x83/0x160
         entry_SYSCALL_64_after_hwframe+0x76/0x7e

  -> #0 (&kvm->slots_lock){+.+.}-{3:3}:
         __lock_acquire+0x15ef/0x2e30
         lock_acquire+0xe0/0x260
         __mutex_lock+0x6a/0xb40
         mutex_lock_nested+0x1f/0x30
         set_nx_huge_pages+0x179/0x1e0 [kvm]
         param_attr_store+0x93/0x100
         module_attr_store+0x22/0x40
         sysfs_kf_write+0x81/0xb0
         kernfs_fop_write_iter+0x133/0x1d0
         vfs_write+0x28d/0x380
         ksys_write+0x70/0xe0
         __x64_sys_write+0x1f/0x30
         x64_sys_call+0x281b/0x2e60
         do_syscall_64+0x83/0x160
         entry_SYSCALL_64_after_hwframe+0x76/0x7e

Cc: Chao Gao <[email protected]>
Fixes: 0bf5049 ("KVM: Drop kvm_count_lock and instead protect kvm_usage_count with kvm_lock")
Cc: [email protected]
Reviewed-by: Kai Huang <[email protected]>
Acked-by: Kai Huang <[email protected]>
Tested-by: Farrah Chen <[email protected]>
Signed-off-by: Sean Christopherson <[email protected]>
Message-ID: <[email protected]>
Signed-off-by: Paolo Bonzini <[email protected]>
kdave pushed a commit that referenced this pull request Oct 14, 2024
On the node of an NFS client, some files saved in the mountpoint of the
NFS server were copied to another location of the same NFS server.
Accidentally, the nfs42_complete_copies() got a NULL-pointer dereference
crash with the following syslog:

[232064.838881] NFSv4: state recovery failed for open file nfs/pvc-12b5200d-cd0f-46a3-b9f0-af8f4fe0ef64.qcow2, error = -116
[232064.839360] NFSv4: state recovery failed for open file nfs/pvc-12b5200d-cd0f-46a3-b9f0-af8f4fe0ef64.qcow2, error = -116
[232066.588183] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000058
[232066.588586] Mem abort info:
[232066.588701]   ESR = 0x0000000096000007
[232066.588862]   EC = 0x25: DABT (current EL), IL = 32 bits
[232066.589084]   SET = 0, FnV = 0
[232066.589216]   EA = 0, S1PTW = 0
[232066.589340]   FSC = 0x07: level 3 translation fault
[232066.589559] Data abort info:
[232066.589683]   ISV = 0, ISS = 0x00000007
[232066.589842]   CM = 0, WnR = 0
[232066.589967] user pgtable: 64k pages, 48-bit VAs, pgdp=00002000956ff400
[232066.590231] [0000000000000058] pgd=08001100ae100003, p4d=08001100ae100003, pud=08001100ae100003, pmd=08001100b3c00003, pte=0000000000000000
[232066.590757] Internal error: Oops: 96000007 [#1] SMP
[232066.590958] Modules linked in: rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache netfs ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm vhost_net vhost vhost_iotlb tap tun ipt_rpfilter xt_multiport ip_set_hash_ip ip_set_hash_net xfrm_interface xfrm6_tunnel tunnel4 tunnel6 esp4 ah4 wireguard libcurve25519_generic veth xt_addrtype xt_set nf_conntrack_netlink ip_set_hash_ipportnet ip_set_hash_ipportip ip_set_bitmap_port ip_set_hash_ipport dummy ip_set ip_vs_sh ip_vs_wrr ip_vs_rr ip_vs iptable_filter sch_ingress nfnetlink_cttimeout vport_gre ip_gre ip_tunnel gre vport_geneve geneve vport_vxlan vxlan ip6_udp_tunnel udp_tunnel openvswitch nf_conncount dm_round_robin dm_service_time dm_multipath xt_nat xt_MASQUERADE nft_chain_nat nf_nat xt_mark xt_conntrack xt_comment nft_compat nft_counter nf_tables nfnetlink ocfs2 ocfs2_nodemanager ocfs2_stackglue iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ipmi_ssif nbd overlay 8021q garp mrp bonding tls rfkill sunrpc ext4 mbcache jbd2
[232066.591052]  vfat fat cas_cache cas_disk ses enclosure scsi_transport_sas sg acpi_ipmi ipmi_si ipmi_devintf ipmi_msghandler ip_tables vfio_pci vfio_pci_core vfio_virqfd vfio_iommu_type1 vfio dm_mirror dm_region_hash dm_log dm_mod nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 br_netfilter bridge stp llc fuse xfs libcrc32c ast drm_vram_helper qla2xxx drm_kms_helper syscopyarea crct10dif_ce sysfillrect ghash_ce sysimgblt sha2_ce fb_sys_fops cec sha256_arm64 sha1_ce drm_ttm_helper ttm nvme_fc igb sbsa_gwdt nvme_fabrics drm nvme_core i2c_algo_bit i40e scsi_transport_fc megaraid_sas aes_neon_bs
[232066.596953] CPU: 6 PID: 4124696 Comm: 10.253.166.125- Kdump: loaded Not tainted 5.15.131-9.cl9_ocfs2.aarch64 #1
[232066.597356] Hardware name: Great Wall .\x93\x8e...RF6260 V5/GWMSSE2GL1T, BIOS T656FBE_V3.0.18 2024-01-06
[232066.597721] pstate: 20400009 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[232066.598034] pc : nfs4_reclaim_open_state+0x220/0x800 [nfsv4]
[232066.598327] lr : nfs4_reclaim_open_state+0x12c/0x800 [nfsv4]
[232066.598595] sp : ffff8000f568fc70
[232066.598731] x29: ffff8000f568fc70 x28: 0000000000001000 x27: ffff21003db33000
[232066.599030] x26: ffff800005521ae0 x25: ffff0100f98fa3f0 x24: 0000000000000001
[232066.599319] x23: ffff800009920008 x22: ffff21003db33040 x21: ffff21003db33050
[232066.599628] x20: ffff410172fe9e40 x19: ffff410172fe9e00 x18: 0000000000000000
[232066.599914] x17: 0000000000000000 x16: 0000000000000004 x15: 0000000000000000
[232066.600195] x14: 0000000000000000 x13: ffff800008e685a8 x12: 00000000eac0c6e6
[232066.600498] x11: 0000000000000000 x10: 0000000000000008 x9 : ffff8000054e5828
[232066.600784] x8 : 00000000ffffffbf x7 : 0000000000000001 x6 : 000000000a9eb14a
[232066.601062] x5 : 0000000000000000 x4 : ffff70ff8a14a800 x3 : 0000000000000058
[232066.601348] x2 : 0000000000000001 x1 : 54dce46366daa6c6 x0 : 0000000000000000
[232066.601636] Call trace:
[232066.601749]  nfs4_reclaim_open_state+0x220/0x800 [nfsv4]
[232066.601998]  nfs4_do_reclaim+0x1b8/0x28c [nfsv4]
[232066.602218]  nfs4_state_manager+0x928/0x10f0 [nfsv4]
[232066.602455]  nfs4_run_state_manager+0x78/0x1b0 [nfsv4]
[232066.602690]  kthread+0x110/0x114
[232066.602830]  ret_from_fork+0x10/0x20
[232066.602985] Code: 1400000d f9403f20 f9402e61 91016003 (f9402c00)
[232066.603284] SMP: stopping secondary CPUs
[232066.606936] Starting crashdump kernel...
[232066.607146] Bye!

Analysing the vmcore, we know that nfs4_copy_state listed by destination
nfs_server->ss_copies was added by the field copies in handle_async_copy(),
and we found a waiting copy process with the stack as:
PID: 3511963  TASK: ffff710028b47e00  CPU: 0   COMMAND: "cp"
 #0 [ffff8001116ef740] __switch_to at ffff8000081b92f4
 #1 [ffff8001116ef760] __schedule at ffff800008dd0650
 #2 [ffff8001116ef7c0] schedule at ffff800008dd0a00
 #3 [ffff8001116ef7e0] schedule_timeout at ffff800008dd6aa0
 #4 [ffff8001116ef860] __wait_for_common at ffff800008dd166c
 #5 [ffff8001116ef8e0] wait_for_completion_interruptible at ffff800008dd1898
 #6 [ffff8001116ef8f0] handle_async_copy at ffff8000055142f4 [nfsv4]
 #7 [ffff8001116ef970] _nfs42_proc_copy at ffff8000055147c8 [nfsv4]
 #8 [ffff8001116efa80] nfs42_proc_copy at ffff800005514cf0 [nfsv4]
 #9 [ffff8001116efc50] __nfs4_copy_file_range.constprop.0 at ffff8000054ed694 [nfsv4]

The NULL-pointer dereference was due to nfs42_complete_copies() listed
the nfs_server->ss_copies by the field ss_copies of nfs4_copy_state.
So the nfs4_copy_state address ffff0100f98fa3f0 was offset by 0x10 and
the data accessed through this pointer was also incorrect. Generally,
the ordered list nfs4_state_owner->so_states indicate open(O_RDWR) or
open(O_WRITE) states are reclaimed firstly by nfs4_reclaim_open_state().
When destination state reclaim is failed with NFS_STATE_RECOVERY_FAILED
and copies are not deleted in nfs_server->ss_copies, the source state
may be passed to the nfs42_complete_copies() process earlier, resulting
in this crash scene finally. To solve this issue, we add a list_head
nfs_server->ss_src_copies for a server-to-server copy specially.

Fixes: 0e65a32 ("NFS: handle source server reboot")
Signed-off-by: Yanjun Zhang <[email protected]>
Reviewed-by: Trond Myklebust <[email protected]>
Signed-off-by: Anna Schumaker <[email protected]>
kdave pushed a commit that referenced this pull request Oct 17, 2024
Syzkaller reported a lockdep splat:

  ============================================
  WARNING: possible recursive locking detected
  6.11.0-rc6-syzkaller-00019-g67784a74e258 #0 Not tainted
  --------------------------------------------
  syz-executor364/5113 is trying to acquire lock:
  ffff8880449f1958 (k-slock-AF_INET){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
  ffff8880449f1958 (k-slock-AF_INET){+.-.}-{2:2}, at: sk_clone_lock+0x2cd/0xf40 net/core/sock.c:2328

  but task is already holding lock:
  ffff88803fe3cb58 (k-slock-AF_INET){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
  ffff88803fe3cb58 (k-slock-AF_INET){+.-.}-{2:2}, at: sk_clone_lock+0x2cd/0xf40 net/core/sock.c:2328

  other info that might help us debug this:
   Possible unsafe locking scenario:

         CPU0
         ----
    lock(k-slock-AF_INET);
    lock(k-slock-AF_INET);

   *** DEADLOCK ***

   May be due to missing lock nesting notation

  7 locks held by syz-executor364/5113:
   #0: ffff8880449f0e18 (sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1607 [inline]
   #0: ffff8880449f0e18 (sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_sendmsg+0x153/0x1b10 net/mptcp/protocol.c:1806
   #1: ffff88803fe39ad8 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1607 [inline]
   #1: ffff88803fe39ad8 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_sendmsg_fastopen+0x11f/0x530 net/mptcp/protocol.c:1727
   #2: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
   #2: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
   #2: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: __ip_queue_xmit+0x5f/0x1b80 net/ipv4/ip_output.c:470
   #3: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
   #3: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
   #3: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x45f/0x1390 net/ipv4/ip_output.c:228
   #4: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline]
   #4: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x33b/0x15b0 net/core/dev.c:6104
   #5: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
   #5: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
   #5: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: ip_local_deliver_finish+0x230/0x5f0 net/ipv4/ip_input.c:232
   #6: ffff88803fe3cb58 (k-slock-AF_INET){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
   #6: ffff88803fe3cb58 (k-slock-AF_INET){+.-.}-{2:2}, at: sk_clone_lock+0x2cd/0xf40 net/core/sock.c:2328

  stack backtrace:
  CPU: 0 UID: 0 PID: 5113 Comm: syz-executor364 Not tainted 6.11.0-rc6-syzkaller-00019-g67784a74e258 #0
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
  Call Trace:
   <IRQ>
   __dump_stack lib/dump_stack.c:93 [inline]
   dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
   check_deadlock kernel/locking/lockdep.c:3061 [inline]
   validate_chain+0x15d3/0x5900 kernel/locking/lockdep.c:3855
   __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142
   lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
   __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
   _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
   spin_lock include/linux/spinlock.h:351 [inline]
   sk_clone_lock+0x2cd/0xf40 net/core/sock.c:2328
   mptcp_sk_clone_init+0x32/0x13c0 net/mptcp/protocol.c:3279
   subflow_syn_recv_sock+0x931/0x1920 net/mptcp/subflow.c:874
   tcp_check_req+0xfe4/0x1a20 net/ipv4/tcp_minisocks.c:853
   tcp_v4_rcv+0x1c3e/0x37f0 net/ipv4/tcp_ipv4.c:2267
   ip_protocol_deliver_rcu+0x22e/0x440 net/ipv4/ip_input.c:205
   ip_local_deliver_finish+0x341/0x5f0 net/ipv4/ip_input.c:233
   NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314
   NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314
   __netif_receive_skb_one_core net/core/dev.c:5661 [inline]
   __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5775
   process_backlog+0x662/0x15b0 net/core/dev.c:6108
   __napi_poll+0xcb/0x490 net/core/dev.c:6772
   napi_poll net/core/dev.c:6841 [inline]
   net_rx_action+0x89b/0x1240 net/core/dev.c:6963
   handle_softirqs+0x2c4/0x970 kernel/softirq.c:554
   do_softirq+0x11b/0x1e0 kernel/softirq.c:455
   </IRQ>
   <TASK>
   __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382
   local_bh_enable include/linux/bottom_half.h:33 [inline]
   rcu_read_unlock_bh include/linux/rcupdate.h:908 [inline]
   __dev_queue_xmit+0x1763/0x3e90 net/core/dev.c:4450
   dev_queue_xmit include/linux/netdevice.h:3105 [inline]
   neigh_hh_output include/net/neighbour.h:526 [inline]
   neigh_output include/net/neighbour.h:540 [inline]
   ip_finish_output2+0xd41/0x1390 net/ipv4/ip_output.c:235
   ip_local_out net/ipv4/ip_output.c:129 [inline]
   __ip_queue_xmit+0x118c/0x1b80 net/ipv4/ip_output.c:535
   __tcp_transmit_skb+0x2544/0x3b30 net/ipv4/tcp_output.c:1466
   tcp_rcv_synsent_state_process net/ipv4/tcp_input.c:6542 [inline]
   tcp_rcv_state_process+0x2c32/0x4570 net/ipv4/tcp_input.c:6729
   tcp_v4_do_rcv+0x77d/0xc70 net/ipv4/tcp_ipv4.c:1934
   sk_backlog_rcv include/net/sock.h:1111 [inline]
   __release_sock+0x214/0x350 net/core/sock.c:3004
   release_sock+0x61/0x1f0 net/core/sock.c:3558
   mptcp_sendmsg_fastopen+0x1ad/0x530 net/mptcp/protocol.c:1733
   mptcp_sendmsg+0x1884/0x1b10 net/mptcp/protocol.c:1812
   sock_sendmsg_nosec net/socket.c:730 [inline]
   __sock_sendmsg+0x1a6/0x270 net/socket.c:745
   ____sys_sendmsg+0x525/0x7d0 net/socket.c:2597
   ___sys_sendmsg net/socket.c:2651 [inline]
   __sys_sendmmsg+0x3b2/0x740 net/socket.c:2737
   __do_sys_sendmmsg net/socket.c:2766 [inline]
   __se_sys_sendmmsg net/socket.c:2763 [inline]
   __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2763
   do_syscall_x64 arch/x86/entry/common.c:52 [inline]
   do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
   entry_SYSCALL_64_after_hwframe+0x77/0x7f
  RIP: 0033:0x7f04fb13a6b9
  Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 01 1a 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
  RSP: 002b:00007ffd651f42d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
  RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f04fb13a6b9
  RDX: 0000000000000001 RSI: 0000000020000d00 RDI: 0000000000000004
  RBP: 00007ffd651f4310 R08: 0000000000000001 R09: 0000000000000001
  R10: 0000000020000080 R11: 0000000000000246 R12: 00000000000f4240
  R13: 00007f04fb187449 R14: 00007ffd651f42f4 R15: 00007ffd651f4300
   </TASK>

As noted by Cong Wang, the splat is false positive, but the code
path leading to the report is an unexpected one: a client is
attempting an MPC handshake towards the in-kernel listener created
by the in-kernel PM for a port based signal endpoint.

Such connection will be never accepted; many of them can make the
listener queue full and preventing the creation of MPJ subflow via
such listener - its intended role.

Explicitly detect this scenario at initial-syn time and drop the
incoming MPC request.

Fixes: 1729cf1 ("mptcp: create the listening socket for new port")
Cc: [email protected]
Reported-by: [email protected]
Closes: https://syzkaller.appspot.com/bug?extid=f4aacdfef2c6a6529c3e
Cc: Cong Wang <[email protected]>
Signed-off-by: Paolo Abeni <[email protected]>
Reviewed-by: Matthieu Baerts (NGI0) <[email protected]>
Reviewed-by: Mat Martineau <[email protected]>
Signed-off-by: Matthieu Baerts (NGI0) <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
kdave pushed a commit that referenced this pull request Oct 21, 2024
…/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 fixes for 6.12, take #3

- Stop wasting space in the HYP idmap, as we are dangerously close
  to the 4kB limit, and this has already exploded in -next

- Fix another race in vgic_init()

- Fix a UBSAN error when faking the cache topology with MTE
  enabled
kdave pushed a commit that referenced this pull request Nov 1, 2024
Hou Tao says:

====================
The patch set fixes several issues in bits iterator. Patch #1 fixes the
kmemleak problem of bits iterator. Patch #2~#3 fix the overflow problem
of nr_bits. Patch #4 fixes the potential stack corruption when bits
iterator is used on 32-bit host. Patch #5 adds more test cases for bits
iterator.

Please see the individual patches for more details. And comments are
always welcome.
---
v4:
 * patch #1: add ack from Yafang
 * patch #3: revert code-churn like changes:
   (1) compute nr_bytes and nr_bits before the check of nr_words.
   (2) use nr_bits == 64 to check for single u64, preventing build
       warning on 32-bit hosts.
 * patch #4: use "BITS_PER_LONG == 32" instead of "!defined(CONFIG_64BIT)"

v3: https://lore.kernel.org/bpf/[email protected]/T/#t
  * split the bits-iterator related patches from "Misc fixes for bpf"
    patch set
  * patch #1: use "!nr_bits || bits >= nr_bits" to stop the iteration
  * patch #2: add a new helper for the overflow problem
  * patch #3: decrease the limitation from 512 to 511 and check whether
    nr_bytes is too large for bpf memory allocator explicitly
  * patch #5: add two more test cases for bit iterator

v2: http://lore.kernel.org/bpf/[email protected]
====================

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>
kdave pushed a commit that referenced this pull request Nov 1, 2024
Petr Machata says:

====================
mlxsw: Fixes

In this patchset:

- Tx header should be pushed for each packet which is transmitted via
  Spectrum ASICs. Patch #1 adds a missing call to skb_cow_head() to make
  sure that there is both enough room to push the Tx header and that the
  SKB header is not cloned and can be modified.

- Commit b5b60bb ("mlxsw: pci: Use page pool for Rx buffers
  allocation") converted mlxsw to use page pool for Rx buffers allocation.
  Sync for CPU and for device should be done for Rx pages. In patches #2
  and #3, add the missing calls to sync pages for, respectively, CPU and
  the device.

- Patch #4 then fixes a bug to IPv6 GRE forwarding offload. Patch #5 adds
  a generic forwarding test that fails with mlxsw ports prior to the fix.
====================

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
kdave pushed a commit that referenced this pull request Nov 20, 2024
Ran Xiaokai reports that with a KCSAN-enabled PREEMPT_RT kernel, we can see
splats like:

| BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48
| in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 0, name: swapper/1
| preempt_count: 10002, expected: 0
| RCU nest depth: 0, expected: 0
| no locks held by swapper/1/0.
| irq event stamp: 156674
| hardirqs last  enabled at (156673): [<ffffffff81130bd9>] do_idle+0x1f9/0x240
| hardirqs last disabled at (156674): [<ffffffff82254f84>] sysvec_apic_timer_interrupt+0x14/0xc0
| softirqs last  enabled at (0): [<ffffffff81099f47>] copy_process+0xfc7/0x4b60
| softirqs last disabled at (0): [<0000000000000000>] 0x0
| Preemption disabled at:
| [<ffffffff814a3e2a>] paint_ptr+0x2a/0x90
| CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.11.0+ #3
| Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-0-ga698c8995f-prebuilt.qemu.org 04/01/2014
| Call Trace:
|  <IRQ>
|  dump_stack_lvl+0x7e/0xc0
|  dump_stack+0x1d/0x30
|  __might_resched+0x1a2/0x270
|  rt_spin_lock+0x68/0x170
|  kcsan_skip_report_debugfs+0x43/0xe0
|  print_report+0xb5/0x590
|  kcsan_report_known_origin+0x1b1/0x1d0
|  kcsan_setup_watchpoint+0x348/0x650
|  __tsan_unaligned_write1+0x16d/0x1d0
|  hrtimer_interrupt+0x3d6/0x430
|  __sysvec_apic_timer_interrupt+0xe8/0x3a0
|  sysvec_apic_timer_interrupt+0x97/0xc0
|  </IRQ>

On a detected data race, KCSAN's reporting logic checks if it should
filter the report. That list is protected by the report_filterlist_lock
*non-raw* spinlock which may sleep on RT kernels.

Since KCSAN may report data races in any context, convert it to a
raw_spinlock.

This requires being careful about when to allocate memory for the filter
list itself which can be done via KCSAN's debugfs interface. Concurrent
modification of the filter list via debugfs should be rare: the chosen
strategy is to optimistically pre-allocate memory before the critical
section and discard if unused.

Link: https://lore.kernel.org/all/[email protected]/
Reported-by: Ran Xiaokai <[email protected]>
Tested-by: Ran Xiaokai <[email protected]>
Signed-off-by: Marco Elver <[email protected]>
kdave pushed a commit that referenced this pull request Nov 20, 2024
nx842_remove() call of_reconfig_notifier_unregister while holding the
devdata_spinlock. This could lead to an invalid wait context error during
kexec reboot, as of_reconfig_notifier_unregister tries to acquire a read-write
semaphore (check logs) while holding a spinlock.

Move the of_reconfig_notifier_unregister() call before acquiring the
spinlock to prevent this race condition invalid wait contexts during system
shutdown or kexec operations.

Log:

[ BUG: Invalid wait context ]
6.11.0-test2-10547-g684a64bf32b6-dirty torvalds#79 Not tainted
-----------------------------
kexec/61926 is trying to lock:
c000000002d8b590 ((of_reconfig_chain).rwsem){++++}-{4:4}, at: blocking_notifier_chain_unregister+0x44/0xa0
other info that might help us debug this:
context-{5:5}
4 locks held by kexec/61926:
 #0: c000000002926c70 (system_transition_mutex){+.+.}-{4:4}, at: __do_sys_reboot+0xf8/0x2e0
 #1: c00000000291af30 (&dev->mutex){....}-{4:4}, at: device_shutdown+0x160/0x310
 #2: c000000051011938 (&dev->mutex){....}-{4:4}, at: device_shutdown+0x174/0x310
 #3: c000000002d88070 (devdata_mutex){....}-{3:3}, at: nx842_remove+0xac/0x1bc
stack backtrace:
CPU: 2 UID: 0 PID: 61926 Comm: kexec Not tainted 6.11.0-test2-10547-g684a64bf32b6-dirty torvalds#79
Hardware name: IBM,9080-HEX POWER10 (architected) 0x800200 0xf000006 of:IBM,FW1060.00 (NH1060_012) hv:phyp pSeries
Call Trace:
[c0000000bb577400] [c000000001239704] dump_stack_lvl+0xc8/0x130 (unreliable)
[c0000000bb577440] [c000000000248398] __lock_acquire+0xb68/0xf00
[c0000000bb577550] [c000000000248820] lock_acquire.part.0+0xf0/0x2a0
[c0000000bb577670] [c00000000127faa0] down_write+0x70/0x1e0
[c0000000bb5776b0] [c0000000001acea4] blocking_notifier_chain_unregister+0x44/0xa0
[c0000000bb5776e0] [c000000000e2312c] of_reconfig_notifier_unregister+0x2c/0x40
[c0000000bb577700] [c000000000ded24c] nx842_remove+0x148/0x1bc
[c0000000bb577790] [c00000000011a114] vio_bus_remove+0x54/0xc0
[c0000000bb5777c0] [c000000000c1a44c] device_shutdown+0x20c/0x310
[c0000000bb577850] [c0000000001b0ab4] kernel_restart_prepare+0x54/0x70
[c0000000bb577870] [c000000000308718] kernel_kexec+0xa8/0x110
[c0000000bb5778e0] [c0000000001b1144] __do_sys_reboot+0x214/0x2e0
[c0000000bb577a40] [c000000000032f98] system_call_exception+0x148/0x310
[c0000000bb577e50] [c00000000000cedc] system_call_vectored_common+0x15c/0x2ec
--- interrupt: 3000 at 0x7fffa07e7df8
NIP:  00007fffa07e7df8 LR: 00007fffa07e7df8 CTR: 0000000000000000
REGS: c0000000bb577e80 TRAP: 3000   Not tainted  (6.11.0-test2-10547-g684a64bf32b6-dirty)
MSR:  800000000280f033   CR: 48022484  XER: 00000000
IRQMASK: 0
GPR00: 0000000000000058 00007ffff961f1e0 00007fffa08f7100 fffffffffee1dead
GPR04: 0000000028121969 0000000045584543 0000000000000000 0000000000000003
GPR08: 0000000000000003 0000000000000000 0000000000000000 0000000000000000
GPR12: 0000000000000000 00007fffa0a9b360 ffffffffffffffff 0000000000000000
GPR16: 0000000000000001 0000000000000002 0000000000000001 0000000000000001
GPR20: 000000011710f520 0000000000000000 0000000000000000 0000000000000001
GPR24: 0000000129be0480 0000000000000003 0000000000000003 00007ffff961f2b0
GPR28: 00000001170f2d30 00000001170f2d28 00007fffa08f18d0 0000000129be04a0
NIP [00007fffa07e7df8] 0x7fffa07e7df8
LR [00007fffa07e7df8] 0x7fffa07e7df8
--- interrupt: 3000

Suggested-by: Michael Ellerman <[email protected]>
Signed-off-by: Vishal Chourasia <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>
kdave pushed a commit that referenced this pull request Nov 21, 2024
Lockdep gives a false positive splat as it can't distinguish the lock
which is taken by different IRQ descriptors from different IRQ chips
that are organized in a way of a hierarchy:

   ======================================================
   WARNING: possible circular locking dependency detected
   6.12.0-rc5-next-20241101-00148-g9fabf8160b53 torvalds#562 Tainted: G        W
   ------------------------------------------------------
   modprobe/141 is trying to acquire lock:
   ffff899446947868 (intel_soc_pmic_bxtwc:502:(&bxtwc_regmap_config)->lock){+.+.}-{4:4}, at: regmap_update_bits_base+0x33/0x90

   but task is already holding lock:
   ffff899446947c68 (&d->lock){+.+.}-{4:4}, at: __setup_irq+0x682/0x790

   which lock already depends on the new lock.

   -> #3 (&d->lock){+.+.}-{4:4}:
   -> #2 (&desc->request_mutex){+.+.}-{4:4}:
   -> #1 (ipclock){+.+.}-{4:4}:
   -> #0 (intel_soc_pmic_bxtwc:502:(&bxtwc_regmap_config)->lock){+.+.}-{4:4}:

   Chain exists of:
     intel_soc_pmic_bxtwc:502:(&bxtwc_regmap_config)->lock --> &desc->request_mutex --> &d->lock

    Possible unsafe locking scenario:

          CPU0                    CPU1
          ----                    ----
     lock(&d->lock);
                                  lock(&desc->request_mutex);
                                  lock(&d->lock);
     lock(intel_soc_pmic_bxtwc:502:(&bxtwc_regmap_config)->lock);

    *** DEADLOCK ***

   3 locks held by modprobe/141:
    #0: ffff8994419368f8 (&dev->mutex){....}-{4:4}, at: __driver_attach+0xf6/0x250
    #1: ffff89944690b250 (&desc->request_mutex){+.+.}-{4:4}, at: __setup_irq+0x1a2/0x790
    #2: ffff899446947c68 (&d->lock){+.+.}-{4:4}, at: __setup_irq+0x682/0x790

Set a lockdep class when we map the IRQ so that it doesn't warn about
a lockdep bug that doesn't exist.

Fixes: 4af8be6 ("regmap: Convert regmap_irq to use irq_domain")
Signed-off-by: Andy Shevchenko <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Mark Brown <[email protected]>
kdave pushed a commit that referenced this pull request Nov 21, 2024
…dfl()

When getting an LLC CPU mask in the default CPU selection policy,
scx_select_cpu_dfl(), a pointer to the sched_domain is dereferenced
using rcu_read_lock() without holding rcu_read_lock(). Such an unprotected
dereference often causes the following warning and can cause an invalid
memory access in the worst case.

Therefore, protect dereference of a sched_domain pointer using a pair
of rcu_read_lock() and unlock().

[   20.996135] =============================
[   20.996345] WARNING: suspicious RCU usage
[   20.996563] 6.11.0-virtme torvalds#17 Tainted: G        W
[   20.996576] -----------------------------
[   20.996576] kernel/sched/ext.c:3323 suspicious rcu_dereference_check() usage!
[   20.996576]
[   20.996576] other info that might help us debug this:
[   20.996576]
[   20.996576]
[   20.996576] rcu_scheduler_active = 2, debug_locks = 1
[   20.996576] 4 locks held by kworker/8:1/140:
[   20.996576]  #0: ffff8b18c00dd348 ((wq_completion)pm){+.+.}-{0:0}, at: process_one_work+0x4a0/0x590
[   20.996576]  #1: ffffb3da01f67e58 ((work_completion)(&dev->power.work)){+.+.}-{0:0}, at: process_one_work+0x1ba/0x590
[   20.996576]  #2: ffffffffa316f9f0 (&rcu_state.gp_wq){..-.}-{2:2}, at: swake_up_one+0x15/0x60
[   20.996576]  #3: ffff8b1880398a60 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0x59/0x7d0
[   20.996576]
[   20.996576] stack backtrace:
[   20.996576] CPU: 8 UID: 0 PID: 140 Comm: kworker/8:1 Tainted: G        W          6.11.0-virtme torvalds#17
[   20.996576] Tainted: [W]=WARN
[   20.996576] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.16.3-1-1 04/01/2014
[   20.996576] Workqueue: pm pm_runtime_work
[   20.996576] Sched_ext: simple (disabling+all), task: runnable_at=-6ms
[   20.996576] Call Trace:
[   20.996576]  <IRQ>
[   20.996576]  dump_stack_lvl+0x6f/0xb0
[   20.996576]  lockdep_rcu_suspicious.cold+0x4e/0x96
[   20.996576]  scx_select_cpu_dfl+0x234/0x260
[   20.996576]  select_task_rq_scx+0xfb/0x190
[   20.996576]  select_task_rq+0x47/0x110
[   20.996576]  try_to_wake_up+0x110/0x7d0
[   20.996576]  swake_up_one+0x39/0x60
[   20.996576]  rcu_core+0xb08/0xe50
[   20.996576]  ? srso_alias_return_thunk+0x5/0xfbef5
[   20.996576]  ? mark_held_locks+0x40/0x70
[   20.996576]  handle_softirqs+0xd3/0x410
[   20.996576]  irq_exit_rcu+0x78/0xa0
[   20.996576]  sysvec_apic_timer_interrupt+0x73/0x80
[   20.996576]  </IRQ>
[   20.996576]  <TASK>
[   20.996576]  asm_sysvec_apic_timer_interrupt+0x1a/0x20
[   20.996576] RIP: 0010:_raw_spin_unlock_irqrestore+0x36/0x70
[   20.996576] Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 11 b4 36 ff 48 89 df e8 99 0d 37 ff f7 c5 00 02 00 00 75 17 9c 58 f6 c4 02 75 2b <65> ff 0d 5b 55 3c 5e 74 16 5b 5d e9 95 8e 28 00 e8 a5 ee 44 ff 9c
[   20.996576] RSP: 0018:ffffb3da01f67d20 EFLAGS: 00000246
[   20.996576] RAX: 0000000000000002 RBX: ffffffffa4640220 RCX: 0000000000000040
[   20.996576] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffffa1c7b27b
[   20.996576] RBP: 0000000000000246 R08: 0000000000000001 R09: 0000000000000000
[   20.996576] R10: 0000000000000001 R11: 000000000000021c R12: 0000000000000246
[   20.996576] R13: ffff8b1881363958 R14: 0000000000000000 R15: ffff8b1881363800
[   20.996576]  ? _raw_spin_unlock_irqrestore+0x4b/0x70
[   20.996576]  serial_port_runtime_resume+0xd4/0x1a0
[   20.996576]  ? __pfx_serial_port_runtime_resume+0x10/0x10
[   20.996576]  __rpm_callback+0x44/0x170
[   20.996576]  ? __pfx_serial_port_runtime_resume+0x10/0x10
[   20.996576]  rpm_callback+0x55/0x60
[   20.996576]  ? __pfx_serial_port_runtime_resume+0x10/0x10
[   20.996576]  rpm_resume+0x582/0x7b0
[   20.996576]  pm_runtime_work+0x7c/0xb0
[   20.996576]  process_one_work+0x1fb/0x590
[   20.996576]  worker_thread+0x18e/0x350
[   20.996576]  ? __pfx_worker_thread+0x10/0x10
[   20.996576]  kthread+0xe2/0x110
[   20.996576]  ? __pfx_kthread+0x10/0x10
[   20.996576]  ret_from_fork+0x34/0x50
[   20.996576]  ? __pfx_kthread+0x10/0x10
[   20.996576]  ret_from_fork_asm+0x1a/0x30
[   20.996576]  </TASK>
[   21.056592] sched_ext: BPF scheduler "simple" disabled (unregistered from user space)

Signed-off-by: Changwoo Min <[email protected]>
Acked-by: Andrea Righi <[email protected]>
Signed-off-by: Tejun Heo <[email protected]>
kdave pushed a commit that referenced this pull request Nov 24, 2024
Patch series "page allocation tag compression", v4.

This patchset implements several improvements:

1. Gracefully handles module unloading while there are used
   allocations allocated from that module;

2. Provides an option to store page allocation tag references in the
   page flags, removing dependency on page extensions and eliminating the
   memory overhead from storing page allocation references (~0.2% of total
   system memory).  This also improves page allocation performance when
   CONFIG_MEM_ALLOC_PROFILING is enabled by eliminating page extension
   lookup.  Page allocation performance overhead is reduced from 41% to
   5.5%.

Patch #1 introduces mas_for_each_rev() helper function.

Patch #2 introduces shutdown_mem_profiling() helper function to be used
when disabling memory allocation profiling.

Patch #3 copies module tags into virtually contiguous memory which
serves two purposes:

- Lets us deal with the situation when module is unloaded while there
  are still live allocations from that module.  Since we are using a copy
  version of the tags we can safely unload the module.  Space and gaps in
  this contiguous memory are managed using a maple tree.

- Enables simple indexing of the tags in the later patches.

Patch #4 changes the way we allocate virtually contiguous memory for
module tags to reserve only vitrual area and populate physical pages only
as needed at module load time.

Patch #5 abstracts page allocation tag reference to simplify later
changes.

Patch #6 adds compression option to the sysctl.vm.mem_profiling boot
parameter for storing page allocation tag references inside page flags if
they fit.  If the number of available page flag bits is insufficient to
address all kernel allocations, memory allocation profiling gets disabled
with an appropriate warning.


This patch (of 6):

Add mas_for_each_rev() function to iterate maple tree nodes in reverse
order.

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Suren Baghdasaryan <[email protected]>
Suggested-by: Liam R. Howlett <[email protected]>
Reviewed-by: Liam R. Howlett <[email protected]>
Reviewed-by: Pasha Tatashin <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Borislav Petkov (AMD) <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Daniel Gomez <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Dennis Zhou <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: John Hubbard <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Cc: Joonsoo Kim <[email protected]>
Cc: Kalesh Singh <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Kent Overstreet <[email protected]>
Cc: Luis Chamberlain <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Mike Rapoport (Microsoft) <[email protected]>
Cc: Minchan Kim <[email protected]>
Cc: Paul E. McKenney <[email protected]>
Cc: Petr Pavlu <[email protected]>
Cc: Roman Gushchin <[email protected]>
Cc: Sami Tolvanen <[email protected]>
Cc: Sourav Panda <[email protected]>
Cc: Steven Rostedt (Google) <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Thomas Huth <[email protected]>
Cc: Uladzislau Rezki (Sony) <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Xiongwei Song <[email protected]>
Cc: Yu Zhao <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
kdave pushed a commit that referenced this pull request Nov 24, 2024
LTP reported a NULL pointer dereference as followed:

 CPU: 7 UID: 0 PID: 5995 Comm: cat Kdump: loaded Not tainted 6.12.0-rc6+ #3
 Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
 pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
 pc : __pi_strcmp+0x24/0x140
 lr : zcomp_available_show+0x60/0x100 [zram]
 sp : ffff800088b93b90
 x29: ffff800088b93b90 x28: 0000000000000001 x27: 0000000000400cc0
 x26: 0000000000000ffe x25: ffff80007b3e2388 x24: 0000000000000000
 x23: ffff80007b3e2390 x22: ffff0004041a9000 x21: ffff80007b3e2900
 x20: 0000000000000000 x19: 0000000000000000 x18: 0000000000000000
 x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
 x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
 x11: 0000000000000000 x10: ffff80007b3e2900 x9 : ffff80007b3cb280
 x8 : 0101010101010101 x7 : 0000000000000000 x6 : 0000000000000000
 x5 : 0000000000000040 x4 : 0000000000000000 x3 : 00656c722d6f7a6c
 x2 : 0000000000000000 x1 : ffff80007b3e2900 x0 : 0000000000000000
 Call trace:
  __pi_strcmp+0x24/0x140
  comp_algorithm_show+0x40/0x70 [zram]
  dev_attr_show+0x28/0x80
  sysfs_kf_seq_show+0x90/0x140
  kernfs_seq_show+0x34/0x48
  seq_read_iter+0x1d4/0x4e8
  kernfs_fop_read_iter+0x40/0x58
  new_sync_read+0x9c/0x168
  vfs_read+0x1a8/0x1f8
  ksys_read+0x74/0x108
  __arm64_sys_read+0x24/0x38
  invoke_syscall+0x50/0x120
  el0_svc_common.constprop.0+0xc8/0xf0
  do_el0_svc+0x24/0x38
  el0_svc+0x38/0x138
  el0t_64_sync_handler+0xc0/0xc8
  el0t_64_sync+0x188/0x190

The zram->comp_algs[ZRAM_PRIMARY_COMP] can be NULL in zram_add() if
comp_algorithm_set() has not been called.  User can access the zram device
by sysfs after device_add_disk(), so there is a time window to trigger the
NULL pointer dereference.  Move it ahead device_add_disk() to make sure
when user can access the zram device, it is ready.  comp_algorithm_set()
is protected by zram->init_lock in other places and no such problem.

Link: https://lkml.kernel.org/r/[email protected]
Fixes: 7ac07a2 ("zram: preparation for multi-zcomp support")
Signed-off-by: Liu Shixin <[email protected]>
Reviewed-by: Sergey Senozhatsky <[email protected]>
Cc: Jens Axboe <[email protected]>
Cc: Minchan Kim <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
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