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FIXUP: limit fetching to last 500 commits for checkpatch #5

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@okias okias commented Jul 15, 2021

Signed-off-by: David Heidelberg [email protected]

okias pushed a commit that referenced this pull request Jul 16, 2021
…ble pull

On remote cable pull, a zfcp_port keeps its status and only gets
ZFCP_STATUS_PORT_LINK_TEST added. Only after an ADISC timeout, we would
actually start port recovery and remove ZFCP_STATUS_COMMON_UNBLOCKED which
zfcp_sysfs_port_fc_security_show() detected and reported as "unknown"
instead of the old and possibly stale zfcp_port->connection_info.

Add check for ZFCP_STATUS_PORT_LINK_TEST for timely "unknown" report.

Link: https://lore.kernel.org/r/[email protected]
Fixes: a17c784 ("scsi: zfcp: report FC Endpoint Security in sysfs")
Cc: <[email protected]> #5.7+
Reviewed-by: Benjamin Block <[email protected]>
Signed-off-by: Steffen Maier <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>
okias pushed a commit that referenced this pull request Jul 16, 2021
Ulf reported the following KASAN splat after adding some manual hacks
into mmc-utils[1].

 DEBUG: mmc_blk_open: Let's sleep for 10s..
 mmc1: card 0007 removed
 BUG: KASAN: use-after-free in mmc_blk_get+0x58/0xb8
 Read of size 4 at addr ffff00000a394a28 by task mmc/180

 CPU: 2 PID: 180 Comm: mmc Not tainted 5.10.0-rc4-00069-gcc758c8c7127-dirty #5
 Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT)
 Call trace:
  dump_backtrace+0x0/0x2b4
  show_stack+0x18/0x6c
  dump_stack+0xfc/0x168
  print_address_description.constprop.0+0x6c/0x488
  kasan_report+0x118/0x210
  __asan_load4+0x94/0xd0
  mmc_blk_get+0x58/0xb8
  mmc_blk_open+0x7c/0xdc
  __blkdev_get+0x3b4/0x964
  blkdev_get+0x64/0x100
  blkdev_open+0xe8/0x104
  do_dentry_open+0x234/0x61c
  vfs_open+0x54/0x64
  path_openat+0xe04/0x1584
  do_filp_open+0xe8/0x1e4
  do_sys_openat2+0x120/0x230
  __arm64_sys_openat+0xf0/0x15c
  el0_svc_common.constprop.0+0xac/0x234
  do_el0_svc+0x84/0xa0
  el0_sync_handler+0x264/0x270
  el0_sync+0x174/0x180

 Allocated by task 33:
  stack_trace_save+0x9c/0xdc
  kasan_save_stack+0x28/0x60
  __kasan_kmalloc.constprop.0+0xc8/0xf0
  kasan_kmalloc+0x10/0x20
  mmc_blk_alloc_req+0x94/0x4b0
  mmc_blk_probe+0x2d4/0xaa4
  mmc_bus_probe+0x34/0x4c
  really_probe+0x148/0x6e0
  driver_probe_device+0x78/0xec
  __device_attach_driver+0x108/0x16c
  bus_for_each_drv+0xf4/0x15c
  __device_attach+0x168/0x240
  device_initial_probe+0x14/0x20
  bus_probe_device+0xec/0x100
  device_add+0x55c/0xaf0
  mmc_add_card+0x288/0x380
  mmc_attach_sd+0x18c/0x22c
  mmc_rescan+0x444/0x4f0
  process_one_work+0x3b8/0x650
  worker_thread+0xa0/0x724
  kthread+0x218/0x220
  ret_from_fork+0x10/0x38

 Freed by task 33:
  stack_trace_save+0x9c/0xdc
  kasan_save_stack+0x28/0x60
  kasan_set_track+0x28/0x40
  kasan_set_free_info+0x24/0x4c
  __kasan_slab_free+0x100/0x180
  kasan_slab_free+0x14/0x20
  kfree+0xb8/0x46c
  mmc_blk_put+0xe4/0x11c
  mmc_blk_remove_req.part.0+0x6c/0xe4
  mmc_blk_remove+0x368/0x370
  mmc_bus_remove+0x34/0x50
  __device_release_driver+0x228/0x31c
  device_release_driver+0x2c/0x44
  bus_remove_device+0x1e4/0x200
  device_del+0x2b0/0x770
  mmc_remove_card+0xf0/0x150
  mmc_sd_detect+0x9c/0x150
  mmc_rescan+0x110/0x4f0
  process_one_work+0x3b8/0x650
  worker_thread+0xa0/0x724
  kthread+0x218/0x220
  ret_from_fork+0x10/0x38

 The buggy address belongs to the object at ffff00000a394800
  which belongs to the cache kmalloc-1k of size 1024
 The buggy address is located 552 bytes inside of
  1024-byte region [ffff00000a394800, ffff00000a394c00)
 The buggy address belongs to the page:
 page:00000000ff84ed53 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x8a390
 head:00000000ff84ed53 order:3 compound_mapcount:0 compound_pincount:0
 flags: 0x3fffc0000010200(slab|head)
 raw: 03fffc0000010200 dead000000000100 dead000000000122 ffff000009f03800
 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
 page dumped because: kasan: bad access detected

 Memory state around the buggy address:
  ffff00000a394900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff00000a394980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 >ffff00000a394a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                   ^
  ffff00000a394a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff00000a394b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

Looking closer at the problem, it looks like a classic dangling pointer
bug. The 'struct mmc_blk_data' that is used after being freed in
mmc_blk_put() is stashed away in 'md->disk->private_data' via
mmc_blk_alloc_req() but used in mmc_blk_get() because the 'usage' count
isn't properly aligned with the lifetime of the pointer. You'd expect
the 'usage' member to be in sync with the kfree(), and it mostly is,
except that mmc_blk_get() needs to dereference the potentially freed
memory storage for the 'struct mmc_blk_data' stashed away in the
private_data member to look at 'usage' before it actually figures out if
it wants to consider it a valid pointer or not. That's not going to work
if the freed memory has been overwritten by something else after the
free, and KASAN rightly complains here.

To fix the immediate problem, let's set the private_data member to NULL
in mmc_blk_put() so that mmc_blk_get() can consider the object "on the
way out" if the pointer is NULL and not even try to look at 'usage' if
the object isn't going to be around much longer. With that set to NULL
on the last mmc_blk_put(), optimize the get path further and use a kref
underneath the 'open_lock' mutex to only up the reference count if it's
non-zero, i.e.  alive, and otherwise make mmc_blk_get() return NULL,
without actually testing the reference count if we're in the process of
removing the object from the system.

Finally, tighten the locking region on the put side to only be around
the parts that are removing the 'mmc_blk_data' from the system and
publishing that fact to the gendisk and then drop the lock as soon as we
can to avoid holding the lock around code that doesn't need it. This
fixes the KASAN issue.

Cc: Matthias Schiffer <[email protected]>
Cc: Sujit Kautkar <[email protected]>
Cc: Zubin Mithra <[email protected]>
Reported-by: Ulf Hansson <[email protected]>
Link: https://lore.kernel.org/linux-mmc/CAPDyKFryT63Jc7+DXWSpAC19qpZRqFr1orxwYGMuSqx247O8cQ@mail.gmail.com/ [1]
Signed-off-by: Stephen Boyd <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Cc: [email protected]
Signed-off-by: Ulf Hansson <[email protected]>
okias pushed a commit that referenced this pull request Jul 16, 2021
…itch

FPU_STATUS register contains FP exception flags bits which are updated
by core as side-effect of FP instructions but can also be manually
wiggled such as by glibc C99 functions fe{raise,clear,test}except() etc.
To effect the update, the programming model requires OR'ing FWE
bit (31). This bit is write-only and RAZ, meaning it is effectively
auto-cleared after write and thus needs to be set everytime: which
is how glibc implements this.

However there's another usecase of FPU_STATUS update, at the time of
Linux task switch when incoming task value needs to be programmed into
the register. This was added as part of f45ba2b ("ARCv2:
fpu: preserve userspace fpu state") which missed OR'ing FWE bit,
meaning the new value is effectively not being written at all.
This patch remedies that.

Interestingly, this snafu was not caught in interm glibc testing as the
race window which relies on a specific exception bit to be set/clear is
really small specially when it nvolves context switch.
Fortunately this was caught by glibc's math/test-fenv-tls test which
repeatedly set/clear exception flags in a big loop, concurrently in main
program and also in a thread.

Fixes: foss-for-synopsys-dwc-arc-processors/linux#54
Fixes: f45ba2b ("ARCv2: fpu: preserve userspace fpu state")
Cc: [email protected]	#5.6+
Signed-off-by: Vineet Gupta <[email protected]>
@okias okias force-pushed the checkpatch_speedup branch from 4f058ba to 53b0ad1 Compare July 19, 2021 20:07
@okias okias closed this Jul 19, 2021
@okias okias deleted the checkpatch_speedup branch July 20, 2021 12:53
okias pushed a commit that referenced this pull request Jul 30, 2021
We got the following lockdep splat while running xfstests (specifically
btrfs/003 and btrfs/020 in a row) with the new rc.  This was uncovered
by 87579e9 ("loop: use worker per cgroup instead of kworker") which
converted loop to using workqueues, which comes with lockdep
annotations that don't exist with kworkers.  The lockdep splat is as
follows

======================================================
WARNING: possible circular locking dependency detected
5.14.0-rc2-custom+ grate-driver#34 Not tainted
------------------------------------------------------
losetup/156417 is trying to acquire lock:
ffff9c7645b02d38 ((wq_completion)loop0){+.+.}-{0:0}, at: flush_workqueue+0x84/0x600

but task is already holding lock:
ffff9c7647395468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x650 [loop]

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #5 (&lo->lo_mutex){+.+.}-{3:3}:
       __mutex_lock+0xba/0x7c0
       lo_open+0x28/0x60 [loop]
       blkdev_get_whole+0x28/0xf0
       blkdev_get_by_dev.part.0+0x168/0x3c0
       blkdev_open+0xd2/0xe0
       do_dentry_open+0x163/0x3a0
       path_openat+0x74d/0xa40
       do_filp_open+0x9c/0x140
       do_sys_openat2+0xb1/0x170
       __x64_sys_openat+0x54/0x90
       do_syscall_64+0x3b/0x90
       entry_SYSCALL_64_after_hwframe+0x44/0xae

-> #4 (&disk->open_mutex){+.+.}-{3:3}:
       __mutex_lock+0xba/0x7c0
       blkdev_get_by_dev.part.0+0xd1/0x3c0
       blkdev_get_by_path+0xc0/0xd0
       btrfs_scan_one_device+0x52/0x1f0 [btrfs]
       btrfs_control_ioctl+0xac/0x170 [btrfs]
       __x64_sys_ioctl+0x83/0xb0
       do_syscall_64+0x3b/0x90
       entry_SYSCALL_64_after_hwframe+0x44/0xae

-> #3 (uuid_mutex){+.+.}-{3:3}:
       __mutex_lock+0xba/0x7c0
       btrfs_rm_device+0x48/0x6a0 [btrfs]
       btrfs_ioctl+0x2d1c/0x3110 [btrfs]
       __x64_sys_ioctl+0x83/0xb0
       do_syscall_64+0x3b/0x90
       entry_SYSCALL_64_after_hwframe+0x44/0xae

-> #2 (sb_writers#11){.+.+}-{0:0}:
       lo_write_bvec+0x112/0x290 [loop]
       loop_process_work+0x25f/0xcb0 [loop]
       process_one_work+0x28f/0x5d0
       worker_thread+0x55/0x3c0
       kthread+0x140/0x170
       ret_from_fork+0x22/0x30

-> #1 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}:
       process_one_work+0x266/0x5d0
       worker_thread+0x55/0x3c0
       kthread+0x140/0x170
       ret_from_fork+0x22/0x30

-> #0 ((wq_completion)loop0){+.+.}-{0:0}:
       __lock_acquire+0x1130/0x1dc0
       lock_acquire+0xf5/0x320
       flush_workqueue+0xae/0x600
       drain_workqueue+0xa0/0x110
       destroy_workqueue+0x36/0x250
       __loop_clr_fd+0x9a/0x650 [loop]
       lo_ioctl+0x29d/0x780 [loop]
       block_ioctl+0x3f/0x50
       __x64_sys_ioctl+0x83/0xb0
       do_syscall_64+0x3b/0x90
       entry_SYSCALL_64_after_hwframe+0x44/0xae

other info that might help us debug this:
Chain exists of:
  (wq_completion)loop0 --> &disk->open_mutex --> &lo->lo_mutex
 Possible unsafe locking scenario:
       CPU0                    CPU1
       ----                    ----
  lock(&lo->lo_mutex);
                               lock(&disk->open_mutex);
                               lock(&lo->lo_mutex);
  lock((wq_completion)loop0);

 *** DEADLOCK ***
1 lock held by losetup/156417:
 #0: ffff9c7647395468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x650 [loop]

stack backtrace:
CPU: 8 PID: 156417 Comm: losetup Not tainted 5.14.0-rc2-custom+ grate-driver#34
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
Call Trace:
 dump_stack_lvl+0x57/0x72
 check_noncircular+0x10a/0x120
 __lock_acquire+0x1130/0x1dc0
 lock_acquire+0xf5/0x320
 ? flush_workqueue+0x84/0x600
 flush_workqueue+0xae/0x600
 ? flush_workqueue+0x84/0x600
 drain_workqueue+0xa0/0x110
 destroy_workqueue+0x36/0x250
 __loop_clr_fd+0x9a/0x650 [loop]
 lo_ioctl+0x29d/0x780 [loop]
 ? __lock_acquire+0x3a0/0x1dc0
 ? update_dl_rq_load_avg+0x152/0x360
 ? lock_is_held_type+0xa5/0x120
 ? find_held_lock.constprop.0+0x2b/0x80
 block_ioctl+0x3f/0x50
 __x64_sys_ioctl+0x83/0xb0
 do_syscall_64+0x3b/0x90
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f645884de6b

Usually the uuid_mutex exists to protect the fs_devices that map
together all of the devices that match a specific uuid.  In rm_device
we're messing with the uuid of a device, so it makes sense to protect
that here.

However in doing that it pulls in a whole host of lockdep dependencies,
as we call mnt_may_write() on the sb before we grab the uuid_mutex, thus
we end up with the dependency chain under the uuid_mutex being added
under the normal sb write dependency chain, which causes problems with
loop devices.

We don't need the uuid mutex here however.  If we call
btrfs_scan_one_device() before we scratch the super block we will find
the fs_devices and not find the device itself and return EBUSY because
the fs_devices is open.  If we call it after the scratch happens it will
not appear to be a valid btrfs file system.

We do not need to worry about other fs_devices modifying operations here
because we're protected by the exclusive operations locking.

So drop the uuid_mutex here in order to fix the lockdep splat.

Signed-off-by: Josef Bacik <[email protected]>
Signed-off-by: David Sterba <[email protected]>
okias pushed a commit that referenced this pull request Aug 11, 2021
…ble pull

commit 8b3bdd9 upstream.

On remote cable pull, a zfcp_port keeps its status and only gets
ZFCP_STATUS_PORT_LINK_TEST added. Only after an ADISC timeout, we would
actually start port recovery and remove ZFCP_STATUS_COMMON_UNBLOCKED which
zfcp_sysfs_port_fc_security_show() detected and reported as "unknown"
instead of the old and possibly stale zfcp_port->connection_info.

Add check for ZFCP_STATUS_PORT_LINK_TEST for timely "unknown" report.

Link: https://lore.kernel.org/r/[email protected]
Fixes: a17c784 ("scsi: zfcp: report FC Endpoint Security in sysfs")
Cc: <[email protected]> #5.7+
Reviewed-by: Benjamin Block <[email protected]>
Signed-off-by: Steffen Maier <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
okias pushed a commit that referenced this pull request Aug 11, 2021
commit c23a9fd upstream.

Two patches listed below removed ctnetlink_dump_helpinfo call from under
rcu_read_lock. Now its rcu_dereference generates following warning:
=============================
WARNING: suspicious RCU usage
5.13.0+ #5 Not tainted
-----------------------------
net/netfilter/nf_conntrack_netlink.c:221 suspicious rcu_dereference_check() usage!

other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
stack backtrace:
CPU: 1 PID: 2251 Comm: conntrack Not tainted 5.13.0+ #5
Call Trace:
 dump_stack+0x7f/0xa1
 ctnetlink_dump_helpinfo+0x134/0x150 [nf_conntrack_netlink]
 ctnetlink_fill_info+0x2c2/0x390 [nf_conntrack_netlink]
 ctnetlink_dump_table+0x13f/0x370 [nf_conntrack_netlink]
 netlink_dump+0x10c/0x370
 __netlink_dump_start+0x1a7/0x260
 ctnetlink_get_conntrack+0x1e5/0x250 [nf_conntrack_netlink]
 nfnetlink_rcv_msg+0x613/0x993 [nfnetlink]
 netlink_rcv_skb+0x50/0x100
 nfnetlink_rcv+0x55/0x120 [nfnetlink]
 netlink_unicast+0x181/0x260
 netlink_sendmsg+0x23f/0x460
 sock_sendmsg+0x5b/0x60
 __sys_sendto+0xf1/0x160
 __x64_sys_sendto+0x24/0x30
 do_syscall_64+0x36/0x70
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Fixes: 49ca022 ("netfilter: ctnetlink: don't dump ct extensions of unconfirmed conntracks")
Fixes: 0b35f60 ("netfilter: Remove duplicated rcu_read_lock.")
Signed-off-by: Vasily Averin <[email protected]>
Reviewed-by: Florian Westphal <[email protected]>
Signed-off-by: Pablo Neira Ayuso <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
okias pushed a commit that referenced this pull request Aug 11, 2021
commit 546362a upstream.

MHI reads the channel ID from the event ring element sent by the
device which can be any value between 0 and 255. In order to
prevent any out of bound accesses, add a check against the maximum
number of channels supported by the controller and those channels
not configured yet so as to skip processing of that event ring
element.

Link: https://lore.kernel.org/r/[email protected]
Fixes: 1d3173a ("bus: mhi: core: Add support for processing events from client device")
Cc: [email protected] #5.10
Reviewed-by: Hemant Kumar <[email protected]>
Reviewed-by: Manivannan Sadhasivam <[email protected]>
Reviewed-by: Jeffrey Hugo <[email protected]>
Signed-off-by: Bhaumik Bhatt <[email protected]>
Signed-off-by: Manivannan Sadhasivam <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
okias pushed a commit that referenced this pull request Aug 11, 2021
…itch

FPU_STATUS register contains FP exception flags bits which are updated
by core as side-effect of FP instructions but can also be manually
wiggled such as by glibc C99 functions fe{raise,clear,test}except() etc.
To effect the update, the programming model requires OR'ing FWE
bit (31). This bit is write-only and RAZ, meaning it is effectively
auto-cleared after write and thus needs to be set everytime: which
is how glibc implements this.

However there's another usecase of FPU_STATUS update, at the time of
Linux task switch when incoming task value needs to be programmed into
the register. This was added as part of f45ba2b ("ARCv2:
fpu: preserve userspace fpu state") which missed OR'ing FWE bit,
meaning the new value is effectively not being written at all.
This patch remedies that.

Interestingly, this snafu was not caught in interm glibc testing as the
race window which relies on a specific exception bit to be set/clear is
really small specially when it nvolves context switch.
Fortunately this was caught by glibc's math/test-fenv-tls test which
repeatedly set/clear exception flags in a big loop, concurrently in main
program and also in a thread.

Fixes: foss-for-synopsys-dwc-arc-processors/linux#54
Fixes: f45ba2b ("ARCv2: fpu: preserve userspace fpu state")
Cc: [email protected]	#5.6+
Signed-off-by: Vineet Gupta <[email protected]>
okias pushed a commit that referenced this pull request Aug 11, 2021
Ammar reports that he's seeing a lockdep splat on running test/rsrc_tags
from the regression suite:

======================================================
WARNING: possible circular locking dependency detected
5.14.0-rc3-bluetea-test-00249-gc7d102232649 #5 Tainted: G           OE
------------------------------------------------------
kworker/2:4/2684 is trying to acquire lock:
ffff88814bb1c0a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_rsrc_put_work+0x13d/0x1a0

but task is already holding lock:
ffffc90001c6be70 ((work_completion)(&(&ctx->rsrc_put_work)->work)){+.+.}-{0:0}, at: process_one_work+0x1bc/0x530

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 ((work_completion)(&(&ctx->rsrc_put_work)->work)){+.+.}-{0:0}:
       __flush_work+0x31b/0x490
       io_rsrc_ref_quiesce.part.0.constprop.0+0x35/0xb0
       __do_sys_io_uring_register+0x45b/0x1060
       do_syscall_64+0x35/0xb0
       entry_SYSCALL_64_after_hwframe+0x44/0xae

-> #0 (&ctx->uring_lock){+.+.}-{3:3}:
       __lock_acquire+0x119a/0x1e10
       lock_acquire+0xc8/0x2f0
       __mutex_lock+0x86/0x740
       io_rsrc_put_work+0x13d/0x1a0
       process_one_work+0x236/0x530
       worker_thread+0x52/0x3b0
       kthread+0x135/0x160
       ret_from_fork+0x1f/0x30

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock((work_completion)(&(&ctx->rsrc_put_work)->work));
                               lock(&ctx->uring_lock);
                               lock((work_completion)(&(&ctx->rsrc_put_work)->work));
  lock(&ctx->uring_lock);

 *** DEADLOCK ***

2 locks held by kworker/2:4/2684:
 #0: ffff88810004d938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1bc/0x530
 #1: ffffc90001c6be70 ((work_completion)(&(&ctx->rsrc_put_work)->work)){+.+.}-{0:0}, at: process_one_work+0x1bc/0x530

stack backtrace:
CPU: 2 PID: 2684 Comm: kworker/2:4 Tainted: G           OE     5.14.0-rc3-bluetea-test-00249-gc7d102232649 #5
Hardware name: Acer Aspire ES1-421/OLVIA_BE, BIOS V1.05 07/02/2015
Workqueue: events io_rsrc_put_work
Call Trace:
 dump_stack_lvl+0x6a/0x9a
 check_noncircular+0xfe/0x110
 __lock_acquire+0x119a/0x1e10
 lock_acquire+0xc8/0x2f0
 ? io_rsrc_put_work+0x13d/0x1a0
 __mutex_lock+0x86/0x740
 ? io_rsrc_put_work+0x13d/0x1a0
 ? io_rsrc_put_work+0x13d/0x1a0
 ? io_rsrc_put_work+0x13d/0x1a0
 ? process_one_work+0x1ce/0x530
 io_rsrc_put_work+0x13d/0x1a0
 process_one_work+0x236/0x530
 worker_thread+0x52/0x3b0
 ? process_one_work+0x530/0x530
 kthread+0x135/0x160
 ? set_kthread_struct+0x40/0x40
 ret_from_fork+0x1f/0x30

which is due to holding the ctx->uring_lock when flushing existing
pending work, while the pending work flushing may need to grab the uring
lock if we're using IOPOLL.

Fix this by dropping the uring_lock a bit earlier as part of the flush.

Cc: [email protected]
Link: axboe/liburing#404
Tested-by: Ammar Faizi <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
okias pushed a commit that referenced this pull request Aug 19, 2021
We got the following lockdep splat while running xfstests (specifically
btrfs/003 and btrfs/020 in a row) with the new rc.  This was uncovered
by 87579e9 ("loop: use worker per cgroup instead of kworker") which
converted loop to using workqueues, which comes with lockdep
annotations that don't exist with kworkers.  The lockdep splat is as
follows

======================================================
WARNING: possible circular locking dependency detected
5.14.0-rc2-custom+ grate-driver#34 Not tainted
------------------------------------------------------
losetup/156417 is trying to acquire lock:
ffff9c7645b02d38 ((wq_completion)loop0){+.+.}-{0:0}, at: flush_workqueue+0x84/0x600

but task is already holding lock:
ffff9c7647395468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x650 [loop]

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #5 (&lo->lo_mutex){+.+.}-{3:3}:
       __mutex_lock+0xba/0x7c0
       lo_open+0x28/0x60 [loop]
       blkdev_get_whole+0x28/0xf0
       blkdev_get_by_dev.part.0+0x168/0x3c0
       blkdev_open+0xd2/0xe0
       do_dentry_open+0x163/0x3a0
       path_openat+0x74d/0xa40
       do_filp_open+0x9c/0x140
       do_sys_openat2+0xb1/0x170
       __x64_sys_openat+0x54/0x90
       do_syscall_64+0x3b/0x90
       entry_SYSCALL_64_after_hwframe+0x44/0xae

-> #4 (&disk->open_mutex){+.+.}-{3:3}:
       __mutex_lock+0xba/0x7c0
       blkdev_get_by_dev.part.0+0xd1/0x3c0
       blkdev_get_by_path+0xc0/0xd0
       btrfs_scan_one_device+0x52/0x1f0 [btrfs]
       btrfs_control_ioctl+0xac/0x170 [btrfs]
       __x64_sys_ioctl+0x83/0xb0
       do_syscall_64+0x3b/0x90
       entry_SYSCALL_64_after_hwframe+0x44/0xae

-> #3 (uuid_mutex){+.+.}-{3:3}:
       __mutex_lock+0xba/0x7c0
       btrfs_rm_device+0x48/0x6a0 [btrfs]
       btrfs_ioctl+0x2d1c/0x3110 [btrfs]
       __x64_sys_ioctl+0x83/0xb0
       do_syscall_64+0x3b/0x90
       entry_SYSCALL_64_after_hwframe+0x44/0xae

-> #2 (sb_writers#11){.+.+}-{0:0}:
       lo_write_bvec+0x112/0x290 [loop]
       loop_process_work+0x25f/0xcb0 [loop]
       process_one_work+0x28f/0x5d0
       worker_thread+0x55/0x3c0
       kthread+0x140/0x170
       ret_from_fork+0x22/0x30

-> #1 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}:
       process_one_work+0x266/0x5d0
       worker_thread+0x55/0x3c0
       kthread+0x140/0x170
       ret_from_fork+0x22/0x30

-> #0 ((wq_completion)loop0){+.+.}-{0:0}:
       __lock_acquire+0x1130/0x1dc0
       lock_acquire+0xf5/0x320
       flush_workqueue+0xae/0x600
       drain_workqueue+0xa0/0x110
       destroy_workqueue+0x36/0x250
       __loop_clr_fd+0x9a/0x650 [loop]
       lo_ioctl+0x29d/0x780 [loop]
       block_ioctl+0x3f/0x50
       __x64_sys_ioctl+0x83/0xb0
       do_syscall_64+0x3b/0x90
       entry_SYSCALL_64_after_hwframe+0x44/0xae

other info that might help us debug this:
Chain exists of:
  (wq_completion)loop0 --> &disk->open_mutex --> &lo->lo_mutex
 Possible unsafe locking scenario:
       CPU0                    CPU1
       ----                    ----
  lock(&lo->lo_mutex);
                               lock(&disk->open_mutex);
                               lock(&lo->lo_mutex);
  lock((wq_completion)loop0);

 *** DEADLOCK ***
1 lock held by losetup/156417:
 #0: ffff9c7647395468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x650 [loop]

stack backtrace:
CPU: 8 PID: 156417 Comm: losetup Not tainted 5.14.0-rc2-custom+ grate-driver#34
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
Call Trace:
 dump_stack_lvl+0x57/0x72
 check_noncircular+0x10a/0x120
 __lock_acquire+0x1130/0x1dc0
 lock_acquire+0xf5/0x320
 ? flush_workqueue+0x84/0x600
 flush_workqueue+0xae/0x600
 ? flush_workqueue+0x84/0x600
 drain_workqueue+0xa0/0x110
 destroy_workqueue+0x36/0x250
 __loop_clr_fd+0x9a/0x650 [loop]
 lo_ioctl+0x29d/0x780 [loop]
 ? __lock_acquire+0x3a0/0x1dc0
 ? update_dl_rq_load_avg+0x152/0x360
 ? lock_is_held_type+0xa5/0x120
 ? find_held_lock.constprop.0+0x2b/0x80
 block_ioctl+0x3f/0x50
 __x64_sys_ioctl+0x83/0xb0
 do_syscall_64+0x3b/0x90
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f645884de6b

Usually the uuid_mutex exists to protect the fs_devices that map
together all of the devices that match a specific uuid.  In rm_device
we're messing with the uuid of a device, so it makes sense to protect
that here.

However in doing that it pulls in a whole host of lockdep dependencies,
as we call mnt_may_write() on the sb before we grab the uuid_mutex, thus
we end up with the dependency chain under the uuid_mutex being added
under the normal sb write dependency chain, which causes problems with
loop devices.

We don't need the uuid mutex here however.  If we call
btrfs_scan_one_device() before we scratch the super block we will find
the fs_devices and not find the device itself and return EBUSY because
the fs_devices is open.  If we call it after the scratch happens it will
not appear to be a valid btrfs file system.

We do not need to worry about other fs_devices modifying operations here
because we're protected by the exclusive operations locking.

So drop the uuid_mutex here in order to fix the lockdep splat.

Signed-off-by: Josef Bacik <[email protected]>
Signed-off-by: David Sterba <[email protected]>
okias pushed a commit that referenced this pull request Aug 19, 2021
commit 1f9482a upstream.

We can deadlock when rmmod'ing the driver or going through firmware
reset, because the cfg80211_unregister_wdev() has to bring down the link
for us, ... which then grab the same wiphy lock.

nl80211_del_interface() already handles a very similar case, with a nice
description:

        /*
         * We hold RTNL, so this is safe, without RTNL opencount cannot
         * reach 0, and thus the rdev cannot be deleted.
         *
         * We need to do it for the dev_close(), since that will call
         * the netdev notifiers, and we need to acquire the mutex there
         * but don't know if we get there from here or from some other
         * place (e.g. "ip link set ... down").
         */
        mutex_unlock(&rdev->wiphy.mtx);
...

Do similarly for mwifiex teardown, by ensuring we bring the link down
first.

Sample deadlock trace:

[  247.103516] INFO: task rmmod:2119 blocked for more than 123 seconds.
[  247.110630]       Not tainted 5.12.4 #5
[  247.115796] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[  247.124557] task:rmmod           state:D stack:    0 pid: 2119 ppid:  2114 flags:0x00400208
[  247.133905] Call trace:
[  247.136644]  __switch_to+0x130/0x170
[  247.140643]  __schedule+0x714/0xa0c
[  247.144548]  schedule_preempt_disabled+0x88/0xf4
[  247.149714]  __mutex_lock_common+0x43c/0x750
[  247.154496]  mutex_lock_nested+0x5c/0x68
[  247.158884]  cfg80211_netdev_notifier_call+0x280/0x4e0 [cfg80211]
[  247.165769]  raw_notifier_call_chain+0x4c/0x78
[  247.170742]  call_netdevice_notifiers_info+0x68/0xa4
[  247.176305]  __dev_close_many+0x7c/0x138
[  247.180693]  dev_close_many+0x7c/0x10c
[  247.184893]  unregister_netdevice_many+0xfc/0x654
[  247.190158]  unregister_netdevice_queue+0xb4/0xe0
[  247.195424]  _cfg80211_unregister_wdev+0xa4/0x204 [cfg80211]
[  247.201816]  cfg80211_unregister_wdev+0x20/0x2c [cfg80211]
[  247.208016]  mwifiex_del_virtual_intf+0xc8/0x188 [mwifiex]
[  247.214174]  mwifiex_uninit_sw+0x158/0x1b0 [mwifiex]
[  247.219747]  mwifiex_remove_card+0x38/0xa0 [mwifiex]
[  247.225316]  mwifiex_pcie_remove+0xd0/0xe0 [mwifiex_pcie]
[  247.231451]  pci_device_remove+0x50/0xe0
[  247.235849]  device_release_driver_internal+0x110/0x1b0
[  247.241701]  driver_detach+0x5c/0x9c
[  247.245704]  bus_remove_driver+0x84/0xb8
[  247.250095]  driver_unregister+0x3c/0x60
[  247.254486]  pci_unregister_driver+0x2c/0x90
[  247.259267]  cleanup_module+0x18/0xcdc [mwifiex_pcie]

Fixes: a05829a ("cfg80211: avoid holding the RTNL when calling the driver")
Cc: [email protected]
Link: https://lore.kernel.org/linux-wireless/[email protected]/
Link: https://lore.kernel.org/linux-wireless/[email protected]/
Reported-by: Maximilian Luz <[email protected]>
Reported-by: [email protected]
Cc: Johannes Berg <[email protected]>
Signed-off-by: Brian Norris <[email protected]>
Tested-by: Maximilian Luz <[email protected]>
Tested-by: Dave Olsthoorn <[email protected]>
Signed-off-by: Kalle Valo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
okias pushed a commit that referenced this pull request Aug 19, 2021
…ble pull

commit 8b3bdd9 upstream.

On remote cable pull, a zfcp_port keeps its status and only gets
ZFCP_STATUS_PORT_LINK_TEST added. Only after an ADISC timeout, we would
actually start port recovery and remove ZFCP_STATUS_COMMON_UNBLOCKED which
zfcp_sysfs_port_fc_security_show() detected and reported as "unknown"
instead of the old and possibly stale zfcp_port->connection_info.

Add check for ZFCP_STATUS_PORT_LINK_TEST for timely "unknown" report.

Link: https://lore.kernel.org/r/[email protected]
Fixes: a17c784 ("scsi: zfcp: report FC Endpoint Security in sysfs")
Cc: <[email protected]> #5.7+
Reviewed-by: Benjamin Block <[email protected]>
Signed-off-by: Steffen Maier <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
okias pushed a commit that referenced this pull request Aug 19, 2021
commit c23a9fd upstream.

Two patches listed below removed ctnetlink_dump_helpinfo call from under
rcu_read_lock. Now its rcu_dereference generates following warning:
=============================
WARNING: suspicious RCU usage
5.13.0+ #5 Not tainted
-----------------------------
net/netfilter/nf_conntrack_netlink.c:221 suspicious rcu_dereference_check() usage!

other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
stack backtrace:
CPU: 1 PID: 2251 Comm: conntrack Not tainted 5.13.0+ #5
Call Trace:
 dump_stack+0x7f/0xa1
 ctnetlink_dump_helpinfo+0x134/0x150 [nf_conntrack_netlink]
 ctnetlink_fill_info+0x2c2/0x390 [nf_conntrack_netlink]
 ctnetlink_dump_table+0x13f/0x370 [nf_conntrack_netlink]
 netlink_dump+0x10c/0x370
 __netlink_dump_start+0x1a7/0x260
 ctnetlink_get_conntrack+0x1e5/0x250 [nf_conntrack_netlink]
 nfnetlink_rcv_msg+0x613/0x993 [nfnetlink]
 netlink_rcv_skb+0x50/0x100
 nfnetlink_rcv+0x55/0x120 [nfnetlink]
 netlink_unicast+0x181/0x260
 netlink_sendmsg+0x23f/0x460
 sock_sendmsg+0x5b/0x60
 __sys_sendto+0xf1/0x160
 __x64_sys_sendto+0x24/0x30
 do_syscall_64+0x36/0x70
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Fixes: 49ca022 ("netfilter: ctnetlink: don't dump ct extensions of unconfirmed conntracks")
Fixes: 0b35f60 ("netfilter: Remove duplicated rcu_read_lock.")
Signed-off-by: Vasily Averin <[email protected]>
Reviewed-by: Florian Westphal <[email protected]>
Signed-off-by: Pablo Neira Ayuso <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
okias pushed a commit that referenced this pull request Aug 19, 2021
commit 56f6f4c upstream.

Devices such as SDX24 do not have the provision for inband wake
doorbell in the form of channel 127 and instead have a sideband
GPIO for it. Newer devices such as SDX55 or SDX65 support inband
wake method by default. Ensure the functionality is used based on
this such that device wake stays held when a client driver uses
mhi_device_get() API or the equivalent debugfs entry.

Link: https://lore.kernel.org/r/[email protected]
Fixes: e3e5e65 ("bus: mhi: pci_generic: No-Op for device_wake operations")
Cc: [email protected] #5.12
Reviewed-by: Manivannan Sadhasivam <[email protected]>
Signed-off-by: Bhaumik Bhatt <[email protected]>
Signed-off-by: Manivannan Sadhasivam <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
okias pushed a commit that referenced this pull request Aug 19, 2021
commit 546362a upstream.

MHI reads the channel ID from the event ring element sent by the
device which can be any value between 0 and 255. In order to
prevent any out of bound accesses, add a check against the maximum
number of channels supported by the controller and those channels
not configured yet so as to skip processing of that event ring
element.

Link: https://lore.kernel.org/r/[email protected]
Fixes: 1d3173a ("bus: mhi: core: Add support for processing events from client device")
Cc: [email protected] #5.10
Reviewed-by: Hemant Kumar <[email protected]>
Reviewed-by: Manivannan Sadhasivam <[email protected]>
Reviewed-by: Jeffrey Hugo <[email protected]>
Signed-off-by: Bhaumik Bhatt <[email protected]>
Signed-off-by: Manivannan Sadhasivam <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
okias pushed a commit that referenced this pull request Aug 19, 2021
commit b8a97f2 upstream.

The qrtr-mhi client driver assumes that inbound buffers are
automatically allocated and queued by the MHI core, but this
doesn't happen for mhi pci devices since IPCR inbound channel is
not flagged with auto_queue, causing unusable IPCR (qrtr)
feature. Fix that.

Link: https://lore.kernel.org/r/[email protected]
[mani: fixed a spelling mistake in commit description]
Fixes: 855a70c ("bus: mhi: Add MHI PCI support for WWAN modems")
Cc: [email protected] #5.10
Reviewed-by: Hemant kumar <[email protected]>
Reviewed-by: Manivannan Sadhasivam <[email protected]>
Signed-off-by: Loic Poulain <[email protected]>
Signed-off-by: Manivannan Sadhasivam <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
okias pushed a commit that referenced this pull request Aug 19, 2021
commit c018db4 upstream.

Ammar reports that he's seeing a lockdep splat on running test/rsrc_tags
from the regression suite:

======================================================
WARNING: possible circular locking dependency detected
5.14.0-rc3-bluetea-test-00249-gc7d102232649 #5 Tainted: G           OE
------------------------------------------------------
kworker/2:4/2684 is trying to acquire lock:
ffff88814bb1c0a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_rsrc_put_work+0x13d/0x1a0

but task is already holding lock:
ffffc90001c6be70 ((work_completion)(&(&ctx->rsrc_put_work)->work)){+.+.}-{0:0}, at: process_one_work+0x1bc/0x530

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 ((work_completion)(&(&ctx->rsrc_put_work)->work)){+.+.}-{0:0}:
       __flush_work+0x31b/0x490
       io_rsrc_ref_quiesce.part.0.constprop.0+0x35/0xb0
       __do_sys_io_uring_register+0x45b/0x1060
       do_syscall_64+0x35/0xb0
       entry_SYSCALL_64_after_hwframe+0x44/0xae

-> #0 (&ctx->uring_lock){+.+.}-{3:3}:
       __lock_acquire+0x119a/0x1e10
       lock_acquire+0xc8/0x2f0
       __mutex_lock+0x86/0x740
       io_rsrc_put_work+0x13d/0x1a0
       process_one_work+0x236/0x530
       worker_thread+0x52/0x3b0
       kthread+0x135/0x160
       ret_from_fork+0x1f/0x30

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock((work_completion)(&(&ctx->rsrc_put_work)->work));
                               lock(&ctx->uring_lock);
                               lock((work_completion)(&(&ctx->rsrc_put_work)->work));
  lock(&ctx->uring_lock);

 *** DEADLOCK ***

2 locks held by kworker/2:4/2684:
 #0: ffff88810004d938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1bc/0x530
 #1: ffffc90001c6be70 ((work_completion)(&(&ctx->rsrc_put_work)->work)){+.+.}-{0:0}, at: process_one_work+0x1bc/0x530

stack backtrace:
CPU: 2 PID: 2684 Comm: kworker/2:4 Tainted: G           OE     5.14.0-rc3-bluetea-test-00249-gc7d102232649 #5
Hardware name: Acer Aspire ES1-421/OLVIA_BE, BIOS V1.05 07/02/2015
Workqueue: events io_rsrc_put_work
Call Trace:
 dump_stack_lvl+0x6a/0x9a
 check_noncircular+0xfe/0x110
 __lock_acquire+0x119a/0x1e10
 lock_acquire+0xc8/0x2f0
 ? io_rsrc_put_work+0x13d/0x1a0
 __mutex_lock+0x86/0x740
 ? io_rsrc_put_work+0x13d/0x1a0
 ? io_rsrc_put_work+0x13d/0x1a0
 ? io_rsrc_put_work+0x13d/0x1a0
 ? process_one_work+0x1ce/0x530
 io_rsrc_put_work+0x13d/0x1a0
 process_one_work+0x236/0x530
 worker_thread+0x52/0x3b0
 ? process_one_work+0x530/0x530
 kthread+0x135/0x160
 ? set_kthread_struct+0x40/0x40
 ret_from_fork+0x1f/0x30

which is due to holding the ctx->uring_lock when flushing existing
pending work, while the pending work flushing may need to grab the uring
lock if we're using IOPOLL.

Fix this by dropping the uring_lock a bit earlier as part of the flush.

Cc: [email protected]
Link: axboe/liburing#404
Tested-by: Ammar Faizi <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
okias pushed a commit that referenced this pull request Aug 19, 2021
…itch

commit 3a715e8 upstream.

FPU_STATUS register contains FP exception flags bits which are updated
by core as side-effect of FP instructions but can also be manually
wiggled such as by glibc C99 functions fe{raise,clear,test}except() etc.
To effect the update, the programming model requires OR'ing FWE
bit (31). This bit is write-only and RAZ, meaning it is effectively
auto-cleared after write and thus needs to be set everytime: which
is how glibc implements this.

However there's another usecase of FPU_STATUS update, at the time of
Linux task switch when incoming task value needs to be programmed into
the register. This was added as part of f45ba2b ("ARCv2:
fpu: preserve userspace fpu state") which missed OR'ing FWE bit,
meaning the new value is effectively not being written at all.
This patch remedies that.

Interestingly, this snafu was not caught in interm glibc testing as the
race window which relies on a specific exception bit to be set/clear is
really small specially when it nvolves context switch.
Fortunately this was caught by glibc's math/test-fenv-tls test which
repeatedly set/clear exception flags in a big loop, concurrently in main
program and also in a thread.

Fixes: foss-for-synopsys-dwc-arc-processors/linux#54
Fixes: f45ba2b ("ARCv2: fpu: preserve userspace fpu state")
Cc: [email protected]	#5.6+
Signed-off-by: Vineet Gupta <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
okias pushed a commit that referenced this pull request Aug 19, 2021
…itch

commit 3a715e8 upstream.

FPU_STATUS register contains FP exception flags bits which are updated
by core as side-effect of FP instructions but can also be manually
wiggled such as by glibc C99 functions fe{raise,clear,test}except() etc.
To effect the update, the programming model requires OR'ing FWE
bit (31). This bit is write-only and RAZ, meaning it is effectively
auto-cleared after write and thus needs to be set everytime: which
is how glibc implements this.

However there's another usecase of FPU_STATUS update, at the time of
Linux task switch when incoming task value needs to be programmed into
the register. This was added as part of f45ba2b ("ARCv2:
fpu: preserve userspace fpu state") which missed OR'ing FWE bit,
meaning the new value is effectively not being written at all.
This patch remedies that.

Interestingly, this snafu was not caught in interm glibc testing as the
race window which relies on a specific exception bit to be set/clear is
really small specially when it nvolves context switch.
Fortunately this was caught by glibc's math/test-fenv-tls test which
repeatedly set/clear exception flags in a big loop, concurrently in main
program and also in a thread.

Fixes: foss-for-synopsys-dwc-arc-processors/linux#54
Fixes: f45ba2b ("ARCv2: fpu: preserve userspace fpu state")
Cc: [email protected]	#5.6+
Signed-off-by: Vineet Gupta <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
okias pushed a commit that referenced this pull request Aug 19, 2021
commit c23a9fd upstream.

Two patches listed below removed ctnetlink_dump_helpinfo call from under
rcu_read_lock. Now its rcu_dereference generates following warning:
=============================
WARNING: suspicious RCU usage
5.13.0+ #5 Not tainted
-----------------------------
net/netfilter/nf_conntrack_netlink.c:221 suspicious rcu_dereference_check() usage!

other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
stack backtrace:
CPU: 1 PID: 2251 Comm: conntrack Not tainted 5.13.0+ #5
Call Trace:
 dump_stack+0x7f/0xa1
 ctnetlink_dump_helpinfo+0x134/0x150 [nf_conntrack_netlink]
 ctnetlink_fill_info+0x2c2/0x390 [nf_conntrack_netlink]
 ctnetlink_dump_table+0x13f/0x370 [nf_conntrack_netlink]
 netlink_dump+0x10c/0x370
 __netlink_dump_start+0x1a7/0x260
 ctnetlink_get_conntrack+0x1e5/0x250 [nf_conntrack_netlink]
 nfnetlink_rcv_msg+0x613/0x993 [nfnetlink]
 netlink_rcv_skb+0x50/0x100
 nfnetlink_rcv+0x55/0x120 [nfnetlink]
 netlink_unicast+0x181/0x260
 netlink_sendmsg+0x23f/0x460
 sock_sendmsg+0x5b/0x60
 __sys_sendto+0xf1/0x160
 __x64_sys_sendto+0x24/0x30
 do_syscall_64+0x36/0x70
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Fixes: 49ca022 ("netfilter: ctnetlink: don't dump ct extensions of unconfirmed conntracks")
Fixes: 0b35f60 ("netfilter: Remove duplicated rcu_read_lock.")
Signed-off-by: Vasily Averin <[email protected]>
Reviewed-by: Florian Westphal <[email protected]>
Signed-off-by: Pablo Neira Ayuso <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
okias pushed a commit that referenced this pull request Aug 19, 2021
commit 4d14c5c upstream

Calling btrfs_qgroup_reserve_meta_prealloc from
btrfs_delayed_inode_reserve_metadata can result in flushing delalloc
while holding a transaction and delayed node locks. This is deadlock
prone. In the past multiple commits:

 * ae5e070 ("btrfs: qgroup: don't try to wait flushing if we're
already holding a transaction")

 * 6f23277 ("btrfs: qgroup: don't commit transaction when we already
 hold the handle")

Tried to solve various aspects of this but this was always a
whack-a-mole game. Unfortunately those 2 fixes don't solve a deadlock
scenario involving btrfs_delayed_node::mutex. Namely, one thread
can call btrfs_dirty_inode as a result of reading a file and modifying
its atime:

  PID: 6963   TASK: ffff8c7f3f94c000  CPU: 2   COMMAND: "test"
  #0  __schedule at ffffffffa529e07d
  #1  schedule at ffffffffa529e4ff
  #2  schedule_timeout at ffffffffa52a1bdd
  #3  wait_for_completion at ffffffffa529eeea             <-- sleeps with delayed node mutex held
  #4  start_delalloc_inodes at ffffffffc0380db5
  #5  btrfs_start_delalloc_snapshot at ffffffffc0393836
  #6  try_flush_qgroup at ffffffffc03f04b2
  #7  __btrfs_qgroup_reserve_meta at ffffffffc03f5bb6     <-- tries to reserve space and starts delalloc inodes.
  #8  btrfs_delayed_update_inode at ffffffffc03e31aa      <-- acquires delayed node mutex
  grate-driver#9  btrfs_update_inode at ffffffffc0385ba8
 grate-driver#10  btrfs_dirty_inode at ffffffffc038627b               <-- TRANSACTIION OPENED
 grate-driver#11  touch_atime at ffffffffa4cf0000
 grate-driver#12  generic_file_read_iter at ffffffffa4c1f123
 grate-driver#13  new_sync_read at ffffffffa4ccdc8a
 grate-driver#14  vfs_read at ffffffffa4cd0849
 grate-driver#15  ksys_read at ffffffffa4cd0bd1
 grate-driver#16  do_syscall_64 at ffffffffa4a052eb
 grate-driver#17  entry_SYSCALL_64_after_hwframe at ffffffffa540008c

This will cause an asynchronous work to flush the delalloc inodes to
happen which can try to acquire the same delayed_node mutex:

  PID: 455    TASK: ffff8c8085fa4000  CPU: 5   COMMAND: "kworker/u16:30"
  #0  __schedule at ffffffffa529e07d
  #1  schedule at ffffffffa529e4ff
  #2  schedule_preempt_disabled at ffffffffa529e80a
  #3  __mutex_lock at ffffffffa529fdcb                    <-- goes to sleep, never wakes up.
  #4  btrfs_delayed_update_inode at ffffffffc03e3143      <-- tries to acquire the mutex
  #5  btrfs_update_inode at ffffffffc0385ba8              <-- this is the same inode that pid 6963 is holding
  #6  cow_file_range_inline.constprop.78 at ffffffffc0386be7
  #7  cow_file_range at ffffffffc03879c1
  #8  btrfs_run_delalloc_range at ffffffffc038894c
  grate-driver#9  writepage_delalloc at ffffffffc03a3c8f
 grate-driver#10  __extent_writepage at ffffffffc03a4c01
 grate-driver#11  extent_write_cache_pages at ffffffffc03a500b
 grate-driver#12  extent_writepages at ffffffffc03a6de2
 grate-driver#13  do_writepages at ffffffffa4c277eb
 grate-driver#14  __filemap_fdatawrite_range at ffffffffa4c1e5bb
 grate-driver#15  btrfs_run_delalloc_work at ffffffffc0380987         <-- starts running delayed nodes
 grate-driver#16  normal_work_helper at ffffffffc03b706c
 grate-driver#17  process_one_work at ffffffffa4aba4e4
 grate-driver#18  worker_thread at ffffffffa4aba6fd
 grate-driver#19  kthread at ffffffffa4ac0a3d
 grate-driver#20  ret_from_fork at ffffffffa54001ff

To fully address those cases the complete fix is to never issue any
flushing while holding the transaction or the delayed node lock. This
patch achieves it by calling qgroup_reserve_meta directly which will
either succeed without flushing or will fail and return -EDQUOT. In the
latter case that return value is going to be propagated to
btrfs_dirty_inode which will fallback to start a new transaction. That's
fine as the majority of time we expect the inode will have
BTRFS_DELAYED_NODE_INODE_DIRTY flag set which will result in directly
copying the in-memory state.

Fixes: c53e965 ("btrfs: qgroup: try to flush qgroup space when we get -EDQUOT")
CC: [email protected] # 5.10+
Reviewed-by: Qu Wenruo <[email protected]>
Signed-off-by: Nikolay Borisov <[email protected]>
Signed-off-by: David Sterba <[email protected]>
Signed-off-by: Anand Jain <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
okias pushed a commit that referenced this pull request Aug 19, 2021
commit c23a9fd upstream.

Two patches listed below removed ctnetlink_dump_helpinfo call from under
rcu_read_lock. Now its rcu_dereference generates following warning:
=============================
WARNING: suspicious RCU usage
5.13.0+ #5 Not tainted
-----------------------------
net/netfilter/nf_conntrack_netlink.c:221 suspicious rcu_dereference_check() usage!

other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
stack backtrace:
CPU: 1 PID: 2251 Comm: conntrack Not tainted 5.13.0+ #5
Call Trace:
 dump_stack+0x7f/0xa1
 ctnetlink_dump_helpinfo+0x134/0x150 [nf_conntrack_netlink]
 ctnetlink_fill_info+0x2c2/0x390 [nf_conntrack_netlink]
 ctnetlink_dump_table+0x13f/0x370 [nf_conntrack_netlink]
 netlink_dump+0x10c/0x370
 __netlink_dump_start+0x1a7/0x260
 ctnetlink_get_conntrack+0x1e5/0x250 [nf_conntrack_netlink]
 nfnetlink_rcv_msg+0x613/0x993 [nfnetlink]
 netlink_rcv_skb+0x50/0x100
 nfnetlink_rcv+0x55/0x120 [nfnetlink]
 netlink_unicast+0x181/0x260
 netlink_sendmsg+0x23f/0x460
 sock_sendmsg+0x5b/0x60
 __sys_sendto+0xf1/0x160
 __x64_sys_sendto+0x24/0x30
 do_syscall_64+0x36/0x70
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Fixes: 49ca022 ("netfilter: ctnetlink: don't dump ct extensions of unconfirmed conntracks")
Fixes: 0b35f60 ("netfilter: Remove duplicated rcu_read_lock.")
Signed-off-by: Vasily Averin <[email protected]>
Reviewed-by: Florian Westphal <[email protected]>
Signed-off-by: Pablo Neira Ayuso <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
okias pushed a commit that referenced this pull request Aug 30, 2021
Only TDs with status TD_CLEARING_CACHE will be given back after
cache is cleared with a set TR deq command.

xhci_invalidate_cached_td() failed to set the TD_CLEARING_CACHE status
for some cancelled TDs as it assumed an endpoint only needs to clear the
TD it stopped on.

This isn't always true. For example with streams enabled an endpoint may
have several stream rings, each stopping on a different TDs.

Note that if an endpoint has several stream rings, the current code
will still only clear the cache of the stream pointed to by the last
cancelled TD in the cancel list.

This patch only focus on making sure all canceled TDs are given back,
avoiding hung task after device removal.
Another fix to solve clearing the caches of all stream rings with
cancelled TDs is needed, but not as urgent.

This issue was simultanously discovered and debugged by
by Tao Wang, with a slightly different fix proposal.

Fixes: 674f843 ("xhci: split handling halted endpoints into two steps")
Cc: <[email protected]> #5.12
Reported-by: Tao Wang <[email protected]>
Signed-off-by: Mathias Nyman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
okias pushed a commit that referenced this pull request Nov 1, 2021
Patch series "kcov: PREEMPT_RT fixup + misc", v2.

The last patch in series is follow-up to address the PREEMPT_RT issue
within in kcov reported by Clark [1].  Patches 1-3 are smaller things that
I noticed while staring at it.  Patch 4 is small change which makes
replacement in #5 simpler / more obvious.

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

This patch (of 5):

The first example code has includes at the top, the following two
example share that part. The last example (remote coverage collection)
requires the linux/types.h header file due its __aligned_u64 usage.

Add the linux/types.h to the top most example and a comment that the
header files from above are required as it is done in the second
example.

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lore.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Sebastian Andrzej Siewior <[email protected]>
Acked-by: Dmitry Vyukov <[email protected]>
Acked-by: Marco Elver <[email protected]>
Tested-by: Marco Elver <[email protected]>
Reviewed-by: Andrey Konovalov <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Clark Williams <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Stephen Rothwell <[email protected]>
okias pushed a commit that referenced this pull request Nov 7, 2021
Host crashes when pci_enable_atomic_ops_to_root() is called for VFs with
virtual buses. The virtual buses added to SR-IOV have bus->self set to NULL
and host crashes due to this.

  PID: 4481   TASK: ffff89c6941b0000  CPU: 53  COMMAND: "bash"
  ...
   #3 [ffff9a9481713808] oops_end at ffffffffb9025cd6
   #4 [ffff9a9481713828] page_fault_oops at ffffffffb906e417
   #5 [ffff9a9481713888] exc_page_fault at ffffffffb9a0ad14
   #6 [ffff9a94817138b0] asm_exc_page_fault at ffffffffb9c00ace
      [exception RIP: pcie_capability_read_dword+28]
      RIP: ffffffffb952fd5c  RSP: ffff9a9481713960  RFLAGS: 00010246
      RAX: 0000000000000001  RBX: ffff89c6b1096000  RCX: 0000000000000000
      RDX: ffff9a9481713990  RSI: 0000000000000024  RDI: 0000000000000000
      RBP: 0000000000000080   R8: 0000000000000008   R9: ffff89c64341a2f8
      R10: 0000000000000002  R11: 0000000000000000  R12: ffff89c648bab000
      R13: 0000000000000000  R14: 0000000000000000  R15: ffff89c648bab0c8
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
   #7 [ffff9a9481713988] pci_enable_atomic_ops_to_root at ffffffffb95359a6
   #8 [ffff9a94817139c0] bnxt_qplib_determine_atomics at ffffffffc08c1a33 [bnxt_re]
   grate-driver#9 [ffff9a94817139d0] bnxt_re_dev_init at ffffffffc08ba2d1 [bnxt_re]

Per PCIe r5.0, sec 9.3.5.10, the AtomicOp Requester Enable bit in Device
Control 2 is reserved for VFs.  The PF value applies to all associated VFs.

Return -EINVAL if pci_enable_atomic_ops_to_root() is called for a VF.

Link: https://lore.kernel.org/r/[email protected]
Fixes: 35f5ace ("RDMA/bnxt_re: Enable global atomic ops if platform supports")
Fixes: 430a236 ("PCI: Add pci_enable_atomic_ops_to_root()")
Signed-off-by: Selvin Xavier <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Andy Gospodarek <[email protected]>
okias pushed a commit that referenced this pull request Nov 9, 2021
It is generally unsafe to call put_device() with dpm_list_mtx held,
because the given device's release routine may carry out an action
depending on that lock which then may deadlock, so modify the
system-wide suspend and resume of devices to always drop dpm_list_mtx
before calling put_device() (and adjust white space somewhat while
at it).

For instance, this prevents the following splat from showing up in
the kernel log after a system resume in certain configurations:

[ 3290.969514] ======================================================
[ 3290.969517] WARNING: possible circular locking dependency detected
[ 3290.969519] 5.15.0+ #2420 Tainted: G S
[ 3290.969523] ------------------------------------------------------
[ 3290.969525] systemd-sleep/4553 is trying to acquire lock:
[ 3290.969529] ffff888117ab1138 ((wq_completion)hci0#2){+.+.}-{0:0}, at: flush_workqueue+0x87/0x4a0
[ 3290.969554]
               but task is already holding lock:
[ 3290.969556] ffffffff8280fca8 (dpm_list_mtx){+.+.}-{3:3}, at: dpm_resume+0x12e/0x3e0
[ 3290.969571]
               which lock already depends on the new lock.

[ 3290.969573]
               the existing dependency chain (in reverse order) is:
[ 3290.969575]
               -> #3 (dpm_list_mtx){+.+.}-{3:3}:
[ 3290.969583]        __mutex_lock+0x9d/0xa30
[ 3290.969591]        device_pm_add+0x2e/0xe0
[ 3290.969597]        device_add+0x4d5/0x8f0
[ 3290.969605]        hci_conn_add_sysfs+0x43/0xb0 [bluetooth]
[ 3290.969689]        hci_conn_complete_evt.isra.71+0x124/0x750 [bluetooth]
[ 3290.969747]        hci_event_packet+0xd6c/0x28a0 [bluetooth]
[ 3290.969798]        hci_rx_work+0x213/0x640 [bluetooth]
[ 3290.969842]        process_one_work+0x2aa/0x650
[ 3290.969851]        worker_thread+0x39/0x400
[ 3290.969859]        kthread+0x142/0x170
[ 3290.969865]        ret_from_fork+0x22/0x30
[ 3290.969872]
               -> #2 (&hdev->lock){+.+.}-{3:3}:
[ 3290.969881]        __mutex_lock+0x9d/0xa30
[ 3290.969887]        hci_event_packet+0xba/0x28a0 [bluetooth]
[ 3290.969935]        hci_rx_work+0x213/0x640 [bluetooth]
[ 3290.969978]        process_one_work+0x2aa/0x650
[ 3290.969985]        worker_thread+0x39/0x400
[ 3290.969993]        kthread+0x142/0x170
[ 3290.969999]        ret_from_fork+0x22/0x30
[ 3290.970004]
               -> #1 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}:
[ 3290.970013]        process_one_work+0x27d/0x650
[ 3290.970020]        worker_thread+0x39/0x400
[ 3290.970028]        kthread+0x142/0x170
[ 3290.970033]        ret_from_fork+0x22/0x30
[ 3290.970038]
               -> #0 ((wq_completion)hci0#2){+.+.}-{0:0}:
[ 3290.970047]        __lock_acquire+0x15cb/0x1b50
[ 3290.970054]        lock_acquire+0x26c/0x300
[ 3290.970059]        flush_workqueue+0xae/0x4a0
[ 3290.970066]        drain_workqueue+0xa1/0x130
[ 3290.970073]        destroy_workqueue+0x34/0x1f0
[ 3290.970081]        hci_release_dev+0x49/0x180 [bluetooth]
[ 3290.970130]        bt_host_release+0x1d/0x30 [bluetooth]
[ 3290.970195]        device_release+0x33/0x90
[ 3290.970201]        kobject_release+0x63/0x160
[ 3290.970211]        dpm_resume+0x164/0x3e0
[ 3290.970215]        dpm_resume_end+0xd/0x20
[ 3290.970220]        suspend_devices_and_enter+0x1a4/0xba0
[ 3290.970229]        pm_suspend+0x26b/0x310
[ 3290.970236]        state_store+0x42/0x90
[ 3290.970243]        kernfs_fop_write_iter+0x135/0x1b0
[ 3290.970251]        new_sync_write+0x125/0x1c0
[ 3290.970257]        vfs_write+0x360/0x3c0
[ 3290.970263]        ksys_write+0xa7/0xe0
[ 3290.970269]        do_syscall_64+0x3a/0x80
[ 3290.970276]        entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 3290.970284]
               other info that might help us debug this:

[ 3290.970285] Chain exists of:
                 (wq_completion)hci0#2 --> &hdev->lock --> dpm_list_mtx

[ 3290.970297]  Possible unsafe locking scenario:

[ 3290.970299]        CPU0                    CPU1
[ 3290.970300]        ----                    ----
[ 3290.970302]   lock(dpm_list_mtx);
[ 3290.970306]                                lock(&hdev->lock);
[ 3290.970310]                                lock(dpm_list_mtx);
[ 3290.970314]   lock((wq_completion)hci0#2);
[ 3290.970319]
                *** DEADLOCK ***

[ 3290.970321] 7 locks held by systemd-sleep/4553:
[ 3290.970325]  #0: ffff888103bcd448 (sb_writers#4){.+.+}-{0:0}, at: ksys_write+0xa7/0xe0
[ 3290.970341]  #1: ffff888115a14488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x103/0x1b0
[ 3290.970355]  #2: ffff888100f719e0 (kn->active#233){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x10c/0x1b0
[ 3290.970369]  #3: ffffffff82661048 (autosleep_lock){+.+.}-{3:3}, at: state_store+0x12/0x90
[ 3290.970384]  #4: ffffffff82658ac8 (system_transition_mutex){+.+.}-{3:3}, at: pm_suspend+0x9f/0x310
[ 3290.970399]  #5: ffffffff827f2a48 (acpi_scan_lock){+.+.}-{3:3}, at: acpi_suspend_begin+0x4c/0x80
[ 3290.970416]  #6: ffffffff8280fca8 (dpm_list_mtx){+.+.}-{3:3}, at: dpm_resume+0x12e/0x3e0
[ 3290.970428]
               stack backtrace:
[ 3290.970431] CPU: 3 PID: 4553 Comm: systemd-sleep Tainted: G S                5.15.0+ #2420
[ 3290.970438] Hardware name: Dell Inc. XPS 13 9380/0RYJWW, BIOS 1.5.0 06/03/2019
[ 3290.970441] Call Trace:
[ 3290.970446]  dump_stack_lvl+0x44/0x57
[ 3290.970454]  check_noncircular+0x105/0x120
[ 3290.970468]  ? __lock_acquire+0x15cb/0x1b50
[ 3290.970474]  __lock_acquire+0x15cb/0x1b50
[ 3290.970487]  lock_acquire+0x26c/0x300
[ 3290.970493]  ? flush_workqueue+0x87/0x4a0
[ 3290.970503]  ? __raw_spin_lock_init+0x3b/0x60
[ 3290.970510]  ? lockdep_init_map_type+0x58/0x240
[ 3290.970519]  flush_workqueue+0xae/0x4a0
[ 3290.970526]  ? flush_workqueue+0x87/0x4a0
[ 3290.970544]  ? drain_workqueue+0xa1/0x130
[ 3290.970552]  drain_workqueue+0xa1/0x130
[ 3290.970561]  destroy_workqueue+0x34/0x1f0
[ 3290.970572]  hci_release_dev+0x49/0x180 [bluetooth]
[ 3290.970624]  bt_host_release+0x1d/0x30 [bluetooth]
[ 3290.970687]  device_release+0x33/0x90
[ 3290.970695]  kobject_release+0x63/0x160
[ 3290.970705]  dpm_resume+0x164/0x3e0
[ 3290.970710]  ? dpm_resume_early+0x251/0x3b0
[ 3290.970718]  dpm_resume_end+0xd/0x20
[ 3290.970723]  suspend_devices_and_enter+0x1a4/0xba0
[ 3290.970737]  pm_suspend+0x26b/0x310
[ 3290.970746]  state_store+0x42/0x90
[ 3290.970755]  kernfs_fop_write_iter+0x135/0x1b0
[ 3290.970764]  new_sync_write+0x125/0x1c0
[ 3290.970777]  vfs_write+0x360/0x3c0
[ 3290.970785]  ksys_write+0xa7/0xe0
[ 3290.970794]  do_syscall_64+0x3a/0x80
[ 3290.970803]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 3290.970811] RIP: 0033:0x7f41b1328164
[ 3290.970819] Code: 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 80 00 00 00 00 8b 05 4a d2 2c 00 48 63 ff 85 c0 75 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 f3 c3 66 90 55 53 48 89 d5 48 89 f3 48 83
[ 3290.970824] RSP: 002b:00007ffe6ae21b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[ 3290.970831] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f41b1328164
[ 3290.970836] RDX: 0000000000000004 RSI: 000055965e651070 RDI: 0000000000000004
[ 3290.970839] RBP: 000055965e651070 R08: 000055965e64f390 R09: 00007f41b1e3d1c0
[ 3290.970843] R10: 000000000000000a R11: 0000000000000246 R12: 0000000000000004
[ 3290.970846] R13: 0000000000000001 R14: 000055965e64f2b0 R15: 0000000000000004

Cc: All applicable <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>
okias pushed a commit that referenced this pull request Nov 9, 2021
Patch series "Solve silent data loss caused by poisoned page cache (shmem/tmpfs)", v5.

When discussing the patch that splits page cache THP in order to offline
the poisoned page, Noaya mentioned there is a bigger problem [1] that
prevents this from working since the page cache page will be truncated
if uncorrectable errors happen.  By looking this deeper it turns out
this approach (truncating poisoned page) may incur silent data loss for
all non-readonly filesystems if the page is dirty.  It may be worse for
in-memory filesystem, e.g.  shmem/tmpfs since the data blocks are
actually gone.

To solve this problem we could keep the poisoned dirty page in page
cache then notify the users on any later access, e.g.  page fault,
read/write, etc.  The clean page could be truncated as is since they can
be reread from disk later on.

The consequence is the filesystems may find poisoned page and manipulate
it as healthy page since all the filesystems actually don't check if the
page is poisoned or not in all the relevant paths except page fault.  In
general, we need make the filesystems be aware of poisoned page before
we could keep the poisoned page in page cache in order to solve the data
loss problem.

To make filesystems be aware of poisoned page we should consider:

 - The page should be not written back: clearing dirty flag could
   prevent from writeback.

 - The page should not be dropped (it shows as a clean page) by drop
   caches or other callers: the refcount pin from hwpoison could prevent
   from invalidating (called by cache drop, inode cache shrinking, etc),
   but it doesn't avoid invalidation in DIO path.

 - The page should be able to get truncated/hole punched/unlinked: it
   works as it is.

 - Notify users when the page is accessed, e.g. read/write, page fault
   and other paths (compression, encryption, etc).

The scope of the last one is huge since almost all filesystems need do
it once a page is returned from page cache lookup.  There are a couple
of options to do it:

 1. Check hwpoison flag for every path, the most straightforward way.

 2. Return NULL for poisoned page from page cache lookup, the most
    callsites check if NULL is returned, this should have least work I
    think. But the error handling in filesystems just return -ENOMEM,
    the error code will incur confusion to the users obviously.

 3. To improve #2, we could return error pointer, e.g. ERR_PTR(-EIO),
    but this will involve significant amount of code change as well
    since all the paths need check if the pointer is ERR or not just
    like option #1.

I did prototypes for both #1 and #3, but it seems #3 may require more
changes than #1.  For #3 ERR_PTR will be returned so all the callers
need to check the return value otherwise invalid pointer may be
dereferenced, but not all callers really care about the content of the
page, for example, partial truncate which just sets the truncated range
in one page to 0.  So for such paths it needs additional modification if
ERR_PTR is returned.  And if the callers have their own way to handle
the problematic pages we need to add a new FGP flag to tell FGP
functions to return the pointer to the page.

It may happen very rarely, but once it happens the consequence (data
corruption) could be very bad and it is very hard to debug.  It seems
this problem had been slightly discussed before, but seems no action was
taken at that time.  [2]

As the aforementioned investigation, it needs huge amount of work to
solve the potential data loss for all filesystems.  But it is much
easier for in-memory filesystems and such filesystems actually suffer
more than others since even the data blocks are gone due to truncating.
So this patchset starts from shmem/tmpfs by taking option #1.

TODO:
* The unpoison has been broken since commit 0ed950d ("mm,hwpoison: make
  get_hwpoison_page() call get_any_page()"), and this patch series make
  refcount check for unpoisoning shmem page fail.
* Expand to other filesystems.  But I haven't heard feedback from filesystem
  developers yet.

Patch breakdown:
Patch #1: cleanup, depended by patch #2
Patch #2: fix THP with hwpoisoned subpage(s) PMD map bug
Patch #3: coding style cleanup
Patch #4: refactor and preparation.
Patch #5: keep the poisoned page in page cache and handle such case for all
          the paths.
Patch #6: the previous patches unblock page cache THP split, so this patch
          add page cache THP split support.

This patch (of 4):

A minor cleanup to the indent.

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Yang Shi <[email protected]>
Reviewed-by: Naoya Horiguchi <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: Kirill A. Shutemov <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Oscar Salvador <[email protected]>
Cc: Peter Xu <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
okias pushed a commit that referenced this pull request Nov 9, 2021
After removing /dev/kmem, sanitizing /proc/kcore and handling /dev/mem,
this series tackles the last sane way how a VM could accidentially access
logically unplugged memory managed by a virtio-mem device: /proc/vmcore

When dumping memory via "makedumpfile", PG_offline pages, used by
virtio-mem to flag logically unplugged memory, are already properly
excluded; however, especially when accessing/copying /proc/vmcore "the
usual way", we can still end up reading logically unplugged memory part of
a virtio-mem device.

Patch #1-#3 are cleanups.  Patch #4 extends the existing oldmem_pfn_is_ram
mechanism.  Patch #5-#7 are virtio-mem refactorings for patch #8, which
implements the virtio-mem logic to query the state of device blocks.

Patch #8:

"
Although virtio-mem currently supports reading unplugged memory in the
hypervisor, this will change in the future, indicated to the device via
a new feature flag. We similarly sanitized /proc/kcore access recently.
[...]
Distributions that support virtio-mem+kdump have to make sure that the
virtio_mem module will be part of the kdump kernel or the kdump initrd;
dracut was recently [2] extended to include virtio-mem in the generated
initrd. As long as no special kdump kernels are used, this will
automatically make sure that virtio-mem will be around in the kdump initrd
and sanitize /proc/vmcore access -- with dracut.
"

This is the last remaining bit to support
VIRTIO_MEM_F_UNPLUGGED_INACCESSIBLE [3] in the Linux implementation of
virtio-mem.

Note: this is best-effort.  We'll never be able to control what runs
inside the second kernel, really, but we also don't have to care: we only
care about sane setups where we don't want our VM getting zapped once we
touch the wrong memory location while dumping.  While we usually expect
sane setups to use "makedumfile", nothing really speaks against just
copying /proc/vmcore, especially in environments where HWpoisioning isn't
typically expected.  Also, we really don't want to put all our trust
completely on the memmap, so sanitizing also makes sense when just using
"makedumpfile".

[1] https://lkml.kernel.org/r/[email protected]
[2] dracutdevs/dracut#1157
[3] https://lists.oasis-open.org/archives/virtio-comment/202109/msg00021.html

This patch (of 9):

The callback is only used for the vmcore nowadays.

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: David Hildenbrand <[email protected]>
Reviewed-by: Boris Ostrovsky <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Juergen Gross <[email protected]>
Cc: Stefano Stabellini <[email protected]>
Cc: "Michael S. Tsirkin" <[email protected]>
Cc: Jason Wang <[email protected]>
Cc: Dave Young <[email protected]>
Cc: Baoquan He <[email protected]>
Cc: Vivek Goyal <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Oscar Salvador <[email protected]>
Cc: Mike Rapoport <[email protected]>
Cc: "Rafael J. Wysocki" <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Stephen Rothwell <[email protected]>
okias pushed a commit that referenced this pull request Nov 9, 2021
Patch series "kcov: PREEMPT_RT fixup + misc", v2.

The last patch in series is follow-up to address the PREEMPT_RT issue
within in kcov reported by Clark [1].  Patches 1-3 are smaller things that
I noticed while staring at it.  Patch 4 is small change which makes
replacement in #5 simpler / more obvious.

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

This patch (of 5):

The first example code has includes at the top, the following two
example share that part. The last example (remote coverage collection)
requires the linux/types.h header file due its __aligned_u64 usage.

Add the linux/types.h to the top most example and a comment that the
header files from above are required as it is done in the second
example.

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lore.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Sebastian Andrzej Siewior <[email protected]>
Acked-by: Dmitry Vyukov <[email protected]>
Acked-by: Marco Elver <[email protected]>
Tested-by: Marco Elver <[email protected]>
Reviewed-by: Andrey Konovalov <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Clark Williams <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Stephen Rothwell <[email protected]>
okias pushed a commit that referenced this pull request Nov 10, 2021
After removing /dev/kmem, sanitizing /proc/kcore and handling /dev/mem,
this series tackles the last sane way how a VM could accidentially
access logically unplugged memory managed by a virtio-mem device:
/proc/vmcore

When dumping memory via "makedumpfile", PG_offline pages, used by
virtio-mem to flag logically unplugged memory, are already properly
excluded; however, especially when accessing/copying /proc/vmcore "the
usual way", we can still end up reading logically unplugged memory part
of a virtio-mem device.

Patch #1-#3 are cleanups.  Patch #4 extends the existing
oldmem_pfn_is_ram mechanism.  Patch #5-#7 are virtio-mem refactorings
for patch #8, which implements the virtio-mem logic to query the state
of device blocks.

Patch #8:
 "Although virtio-mem currently supports reading unplugged memory in the
  hypervisor, this will change in the future, indicated to the device
  via a new feature flag. We similarly sanitized /proc/kcore access
  recently.
  [...]
  Distributions that support virtio-mem+kdump have to make sure that the
  virtio_mem module will be part of the kdump kernel or the kdump
  initrd; dracut was recently [2] extended to include virtio-mem in the
  generated initrd. As long as no special kdump kernels are used, this
  will automatically make sure that virtio-mem will be around in the
  kdump initrd and sanitize /proc/vmcore access -- with dracut"

This is the last remaining bit to support
VIRTIO_MEM_F_UNPLUGGED_INACCESSIBLE [3] in the Linux implementation of
virtio-mem.

Note: this is best-effort.  We'll never be able to control what runs
inside the second kernel, really, but we also don't have to care: we
only care about sane setups where we don't want our VM getting zapped
once we touch the wrong memory location while dumping.  While we usually
expect sane setups to use "makedumfile", nothing really speaks against
just copying /proc/vmcore, especially in environments where HWpoisioning
isn't typically expected.  Also, we really don't want to put all our
trust completely on the memmap, so sanitizing also makes sense when just
using "makedumpfile".

[1] https://lkml.kernel.org/r/[email protected]
[2] dracutdevs/dracut#1157
[3] https://lists.oasis-open.org/archives/virtio-comment/202109/msg00021.html

This patch (of 9):

The callback is only used for the vmcore nowadays.

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: David Hildenbrand <[email protected]>
Reviewed-by: Boris Ostrovsky <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Juergen Gross <[email protected]>
Cc: Stefano Stabellini <[email protected]>
Cc: "Michael S. Tsirkin" <[email protected]>
Cc: Jason Wang <[email protected]>
Cc: Dave Young <[email protected]>
Cc: Baoquan He <[email protected]>
Cc: Vivek Goyal <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Oscar Salvador <[email protected]>
Cc: Mike Rapoport <[email protected]>
Cc: "Rafael J. Wysocki" <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
okias pushed a commit that referenced this pull request Nov 10, 2021
Patch series "kcov: PREEMPT_RT fixup + misc", v2.

The last patch in series is follow-up to address the PREEMPT_RT issue
within in kcov reported by Clark [1].  Patches 1-3 are smaller things that
I noticed while staring at it.  Patch 4 is small change which makes
replacement in #5 simpler / more obvious.

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

This patch (of 5):

The first example code has includes at the top, the following two
example share that part. The last example (remote coverage collection)
requires the linux/types.h header file due its __aligned_u64 usage.

Add the linux/types.h to the top most example and a comment that the
header files from above are required as it is done in the second
example.

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lore.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Sebastian Andrzej Siewior <[email protected]>
Acked-by: Dmitry Vyukov <[email protected]>
Acked-by: Marco Elver <[email protected]>
Tested-by: Marco Elver <[email protected]>
Reviewed-by: Andrey Konovalov <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Clark Williams <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
okias pushed a commit that referenced this pull request Dec 2, 2021
With preemption enabled (CONFIG_DEBUG_PREEMPT=y), the following appeared
when rnbd client tries to map remote block device.

  BUG: using smp_processor_id() in preemptible [00000000] code: bash/1733
  caller is debug_smp_processor_id+0x17/0x20
  CPU: 0 PID: 1733 Comm: bash Not tainted 5.16.0-rc1 #5
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-0-g155821a-rebuilt.opensuse.org 04/01/2014
  Call Trace:
   <TASK>
   dump_stack_lvl+0x5d/0x78
   dump_stack+0x10/0x12
   check_preemption_disabled+0xe4/0xf0
   debug_smp_processor_id+0x17/0x20
   rtrs_clt_update_all_stats+0x3b/0x70 [rtrs_client]
   rtrs_clt_read_req+0xc3/0x380 [rtrs_client]
   ? rtrs_clt_init_req+0xe3/0x120 [rtrs_client]
   rtrs_clt_request+0x1a7/0x320 [rtrs_client]
   ? 0xffffffffc0ab1000
   send_usr_msg+0xbf/0x160 [rnbd_client]
   ? rnbd_clt_put_sess+0x60/0x60 [rnbd_client]
   ? send_usr_msg+0x160/0x160 [rnbd_client]
   ? sg_alloc_table+0x27/0xb0
   ? sg_zero_buffer+0xd0/0xd0
   send_msg_sess_info+0xe9/0x180 [rnbd_client]
   ? rnbd_clt_put_sess+0x60/0x60 [rnbd_client]
   ? blk_mq_alloc_tag_set+0x2ef/0x370
   rnbd_clt_map_device+0xba8/0xcd0 [rnbd_client]
   ? send_msg_open+0x200/0x200 [rnbd_client]
   rnbd_clt_map_device_store+0x3e5/0x620 [rnbd_client

To supress the calltrace, let's call get_cpu_ptr/put_cpu_ptr pair in
rtrs_clt_update_rdma_stats to disable preemption when accessing per-cpu
variable.

While at it, let's make the similar change in rtrs_clt_update_wc_stats.
And for rtrs_clt_inc_failover_cnt, though it was only called inside rcu
section, but it still can be preempted in case CONFIG_PREEMPT_RCU is
enabled, so change it to {get,put}_cpu_ptr pair either.

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Guoqing Jiang <[email protected]>
Reviewed-by: Leon Romanovsky <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>
okias pushed a commit that referenced this pull request Feb 6, 2022
…aged pages

commit c4dc63f upstream.

In kdump kernel of x86_64, page allocation failure is observed:

 kworker/u2:2: page allocation failure: order:0, mode:0xcc1(GFP_KERNEL|GFP_DMA), nodemask=(null),cpuset=/,mems_allowed=0
 CPU: 0 PID: 55 Comm: kworker/u2:2 Not tainted 5.16.0-rc4+ #5
 Hardware name: AMD Dinar/Dinar, BIOS RDN1505B 06/05/2013
 Workqueue: events_unbound async_run_entry_fn
 Call Trace:
  <TASK>
  dump_stack_lvl+0x48/0x5e
  warn_alloc.cold+0x72/0xd6
  __alloc_pages_slowpath.constprop.0+0xc69/0xcd0
  __alloc_pages+0x1df/0x210
  new_slab+0x389/0x4d0
  ___slab_alloc+0x58f/0x770
  __slab_alloc.constprop.0+0x4a/0x80
  kmem_cache_alloc_trace+0x24b/0x2c0
  sr_probe+0x1db/0x620
  ......
  device_add+0x405/0x920
  ......
  __scsi_add_device+0xe5/0x100
  ata_scsi_scan_host+0x97/0x1d0
  async_run_entry_fn+0x30/0x130
  process_one_work+0x1e8/0x3c0
  worker_thread+0x50/0x3b0
  ? rescuer_thread+0x350/0x350
  kthread+0x16b/0x190
  ? set_kthread_struct+0x40/0x40
  ret_from_fork+0x22/0x30
  </TASK>
 Mem-Info:
 ......

The above failure happened when calling kmalloc() to allocate buffer with
GFP_DMA.  It requests to allocate slab page from DMA zone while no managed
pages at all in there.

 sr_probe()
 --> get_capabilities()
     --> buffer = kmalloc(512, GFP_KERNEL | GFP_DMA);

Because in the current kernel, dma-kmalloc will be created as long as
CONFIG_ZONE_DMA is enabled.  However, kdump kernel of x86_64 doesn't have
managed pages on DMA zone since commit 6f599d8 ("x86/kdump: Always
reserve the low 1M when the crashkernel option is specified").  The
failure can be always reproduced.

For now, let's mute the warning of allocation failure if requesting pages
from DMA zone while no managed pages.

[[email protected]: fix warning]

Link: https://lkml.kernel.org/r/[email protected]
Fixes: 6f599d8 ("x86/kdump: Always reserve the low 1M when the crashkernel option is specified")
Signed-off-by: Baoquan He <[email protected]>
Acked-by: John Donnelly  <[email protected]>
Reviewed-by: Hyeonggon Yoo <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Pekka Enberg <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Joonsoo Kim <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: David Laight <[email protected]>
Cc: Marek Szyprowski <[email protected]>
Cc: Robin Murphy <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
okias pushed a commit that referenced this pull request Feb 6, 2022
commit 35fe7cf upstream.

The below warning is splatting during guest reboot.

  ------------[ cut here ]------------
  WARNING: CPU: 0 PID: 1931 at arch/x86/kvm/x86.c:10322 kvm_arch_vcpu_ioctl_run+0x874/0x880 [kvm]
  CPU: 0 PID: 1931 Comm: qemu-system-x86 Tainted: G          I       5.17.0-rc1+ #5
  RIP: 0010:kvm_arch_vcpu_ioctl_run+0x874/0x880 [kvm]
  Call Trace:
   <TASK>
   kvm_vcpu_ioctl+0x279/0x710 [kvm]
   __x64_sys_ioctl+0x83/0xb0
   do_syscall_64+0x3b/0xc0
   entry_SYSCALL_64_after_hwframe+0x44/0xae
  RIP: 0033:0x7fd39797350b

This can be triggered by not exposing tsc-deadline mode and doing a reboot in
the guest. The lapic_shutdown() function which is called in sys_reboot path
will not disarm the flying timer, it just masks LVTT. lapic_shutdown() clears
APIC state w/ LVT_MASKED and timer-mode bit is 0, this can trigger timer-mode
switch between tsc-deadline and oneshot/periodic, which can result in preemption
timer be cancelled in apic_update_lvtt(). However, We can't depend on this when
not exposing tsc-deadline mode and oneshot/periodic modes emulated by preemption
timer. Qemu will synchronise states around reset, let's cancel preemption timer
under KVM_SET_LAPIC.

Signed-off-by: Wanpeng Li <[email protected]>
Message-Id: <[email protected]>
Cc: [email protected]
Signed-off-by: Paolo Bonzini <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
okias pushed a commit that referenced this pull request Jul 31, 2023
[ Upstream commit 99d4850 ]

Found by leak sanitizer:
```
==1632594==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 21 byte(s) in 1 object(s) allocated from:
    #0 0x7f2953a7077b in __interceptor_strdup ../../../../src/libsanitizer/asan/asan_interceptors.cpp:439
    #1 0x556701d6fbbf in perf_env__read_cpuid util/env.c:369
    #2 0x556701d70589 in perf_env__cpuid util/env.c:465
    #3 0x55670204bba2 in x86__is_amd_cpu arch/x86/util/env.c:14
    #4 0x5567020487a2 in arch__post_evsel_config arch/x86/util/evsel.c:83
    #5 0x556701d8f78b in evsel__config util/evsel.c:1366
    #6 0x556701ef5872 in evlist__config util/record.c:108
    #7 0x556701cd6bcd in test__PERF_RECORD tests/perf-record.c:112
    #8 0x556701cacd07 in run_test tests/builtin-test.c:236
    grate-driver#9 0x556701cacfac in test_and_print tests/builtin-test.c:265
    grate-driver#10 0x556701cadddb in __cmd_test tests/builtin-test.c:402
    grate-driver#11 0x556701caf2aa in cmd_test tests/builtin-test.c:559
    grate-driver#12 0x556701d3b557 in run_builtin tools/perf/perf.c:323
    grate-driver#13 0x556701d3bac8 in handle_internal_command tools/perf/perf.c:377
    grate-driver#14 0x556701d3be90 in run_argv tools/perf/perf.c:421
    grate-driver#15 0x556701d3c3f8 in main tools/perf/perf.c:537
    grate-driver#16 0x7f2952a46189 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58

SUMMARY: AddressSanitizer: 21 byte(s) leaked in 1 allocation(s).
```

Fixes: f7b58cb ("perf mem/c2c: Add load store event mappings for AMD")
Signed-off-by: Ian Rogers <[email protected]>
Acked-by: Ravi Bangoria <[email protected]>
Tested-by: Arnaldo Carvalho de Melo <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ravi Bangoria <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
okias pushed a commit that referenced this pull request Jul 31, 2023
[ Upstream commit b684c09 ]

ppc_save_regs() skips one stack frame while saving the CPU register states.
Instead of saving current R1, it pulls the previous stack frame pointer.

When vmcores caused by direct panic call (such as `echo c >
/proc/sysrq-trigger`), are debugged with gdb, gdb fails to show the
backtrace correctly. On further analysis, it was found that it was because
of mismatch between r1 and NIP.

GDB uses NIP to get current function symbol and uses corresponding debug
info of that function to unwind previous frames, but due to the
mismatching r1 and NIP, the unwinding does not work, and it fails to
unwind to the 2nd frame and hence does not show the backtrace.

GDB backtrace with vmcore of kernel without this patch:

---------
(gdb) bt
 #0  0xc0000000002a53e8 in crash_setup_regs (oldregs=<optimized out>,
    newregs=0xc000000004f8f8d8) at ./arch/powerpc/include/asm/kexec.h:69
 #1  __crash_kexec (regs=<optimized out>) at kernel/kexec_core.c:974
 #2  0x0000000000000063 in ?? ()
 #3  0xc000000003579320 in ?? ()
---------

Further analysis revealed that the mismatch occurred because
"ppc_save_regs" was saving the previous stack's SP instead of the current
r1. This patch fixes this by storing current r1 in the saved pt_regs.

GDB backtrace with vmcore of patched kernel:

--------
(gdb) bt
 #0  0xc0000000002a53e8 in crash_setup_regs (oldregs=0x0, newregs=0xc00000000670b8d8)
    at ./arch/powerpc/include/asm/kexec.h:69
 #1  __crash_kexec (regs=regs@entry=0x0) at kernel/kexec_core.c:974
 #2  0xc000000000168918 in panic (fmt=fmt@entry=0xc000000001654a60 "sysrq triggered crash\n")
    at kernel/panic.c:358
 #3  0xc000000000b735f8 in sysrq_handle_crash (key=<optimized out>) at drivers/tty/sysrq.c:155
 #4  0xc000000000b742cc in __handle_sysrq (key=key@entry=99, check_mask=check_mask@entry=false)
    at drivers/tty/sysrq.c:602
 #5  0xc000000000b7506c in write_sysrq_trigger (file=<optimized out>, buf=<optimized out>,
    count=2, ppos=<optimized out>) at drivers/tty/sysrq.c:1163
 #6  0xc00000000069a7bc in pde_write (ppos=<optimized out>, count=<optimized out>,
    buf=<optimized out>, file=<optimized out>, pde=0xc00000000362cb40) at fs/proc/inode.c:340
 #7  proc_reg_write (file=<optimized out>, buf=<optimized out>, count=<optimized out>,
    ppos=<optimized out>) at fs/proc/inode.c:352
 #8  0xc0000000005b3bbc in vfs_write (file=file@entry=0xc000000006aa6b00,
    buf=buf@entry=0x61f498b4f60 <error: Cannot access memory at address 0x61f498b4f60>,
    count=count@entry=2, pos=pos@entry=0xc00000000670bda0) at fs/read_write.c:582
 grate-driver#9  0xc0000000005b4264 in ksys_write (fd=<optimized out>,
    buf=0x61f498b4f60 <error: Cannot access memory at address 0x61f498b4f60>, count=2)
    at fs/read_write.c:637
 grate-driver#10 0xc00000000002ea2c in system_call_exception (regs=0xc00000000670be80, r0=<optimized out>)
    at arch/powerpc/kernel/syscall.c:171
 grate-driver#11 0xc00000000000c270 in system_call_vectored_common ()
    at arch/powerpc/kernel/interrupt_64.S:192
--------

Nick adds:
  So this now saves regs as though it was an interrupt taken in the
  caller, at the instruction after the call to ppc_save_regs, whereas
  previously the NIP was there, but R1 came from the caller's caller and
  that mismatch is what causes gdb's dwarf unwinder to go haywire.

Signed-off-by: Aditya Gupta <[email protected]>
Fixes: d16a58f ("powerpc: Improve ppc_save_regs()")
Reivewed-by: Nicholas Piggin <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://msgid.link/[email protected]
Signed-off-by: Sasha Levin <[email protected]>
okias pushed a commit that referenced this pull request Dec 4, 2023
When scanning namespaces, it is possible to get valid data from the first
call to nvme_identify_ns() in nvme_alloc_ns(), but not from the second
call in nvme_update_ns_info_block().  In particular, if the NSID becomes
inactive between the two commands, a storage device may return a buffer
filled with zero as per 4.1.5.1.  In this case, we can get a kernel crash
due to a divide-by-zero in blk_stack_limits() because ns->lba_shift will
be set to zero.

PID: 326      TASK: ffff95fec3cd8000  CPU: 29   COMMAND: "kworker/u98:10"
 #0 [ffffad8f8702f9e0] machine_kexec at ffffffff91c76ec7
 #1 [ffffad8f8702fa38] __crash_kexec at ffffffff91dea4fa
 #2 [ffffad8f8702faf8] crash_kexec at ffffffff91deb788
 #3 [ffffad8f8702fb00] oops_end at ffffffff91c2e4bb
 #4 [ffffad8f8702fb20] do_trap at ffffffff91c2a4ce
 #5 [ffffad8f8702fb70] do_error_trap at ffffffff91c2a595
 #6 [ffffad8f8702fbb0] exc_divide_error at ffffffff928506e6
 #7 [ffffad8f8702fbd0] asm_exc_divide_error at ffffffff92a00926
    [exception RIP: blk_stack_limits+434]
    RIP: ffffffff92191872  RSP: ffffad8f8702fc80  RFLAGS: 00010246
    RAX: 0000000000000000  RBX: ffff95efa0c91800  RCX: 0000000000000001
    RDX: 0000000000000000  RSI: 0000000000000001  RDI: 0000000000000001
    RBP: 00000000ffffffff   R8: ffff95fec7df35a8   R9: 0000000000000000
    R10: 0000000000000000  R11: 0000000000000001  R12: 0000000000000000
    R13: 0000000000000000  R14: 0000000000000000  R15: ffff95fed33c09a8
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #8 [ffffad8f8702fce0] nvme_update_ns_info_block at ffffffffc06d3533 [nvme_core]
 grate-driver#9 [ffffad8f8702fd18] nvme_scan_ns at ffffffffc06d6fa7 [nvme_core]

This happened when the check for valid data was moved out of nvme_identify_ns()
into one of the callers.  Fix this by checking in both callers.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=218186
Fixes: 0dd6fff ("nvme: bring back auto-removal of deleted namespaces during sequential scan")
Cc: [email protected]
Signed-off-by: Ewan D. Milne <[email protected]>
Signed-off-by: Keith Busch <[email protected]>
okias pushed a commit that referenced this pull request Dec 18, 2023
Validate next header's offset in ->next_header() so that it isn't
smaller than MID_HEADER_SIZE(server) and then standard_receive3() or
->receive() ends up writing off the end of the buffer because
'pdu_length - MID_HEADER_SIZE(server)' wraps up to a huge length:

  BUG: KASAN: slab-out-of-bounds in _copy_to_iter+0x4fc/0x840
  Write of size 701 at addr ffff88800caf407f by task cifsd/1090

  CPU: 0 PID: 1090 Comm: cifsd Not tainted 6.7.0-rc4 #5
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
  rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014
  Call Trace:
   <TASK>
   dump_stack_lvl+0x4a/0x80
   print_report+0xcf/0x650
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __phys_addr+0x46/0x90
   kasan_report+0xd8/0x110
   ? _copy_to_iter+0x4fc/0x840
   ? _copy_to_iter+0x4fc/0x840
   kasan_check_range+0x105/0x1b0
   __asan_memcpy+0x3c/0x60
   _copy_to_iter+0x4fc/0x840
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? hlock_class+0x32/0xc0
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __pfx__copy_to_iter+0x10/0x10
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? lock_is_held_type+0x90/0x100
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __might_resched+0x278/0x360
   ? __pfx___might_resched+0x10/0x10
   ? srso_alias_return_thunk+0x5/0xfbef5
   __skb_datagram_iter+0x2c2/0x460
   ? __pfx_simple_copy_to_iter+0x10/0x10
   skb_copy_datagram_iter+0x6c/0x110
   tcp_recvmsg_locked+0x9be/0xf40
   ? __pfx_tcp_recvmsg_locked+0x10/0x10
   ? mark_held_locks+0x5d/0x90
   ? srso_alias_return_thunk+0x5/0xfbef5
   tcp_recvmsg+0xe2/0x310
   ? __pfx_tcp_recvmsg+0x10/0x10
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? lock_acquire+0x14a/0x3a0
   ? srso_alias_return_thunk+0x5/0xfbef5
   inet_recvmsg+0xd0/0x370
   ? __pfx_inet_recvmsg+0x10/0x10
   ? __pfx_lock_release+0x10/0x10
   ? do_raw_spin_trylock+0xd1/0x120
   sock_recvmsg+0x10d/0x150
   cifs_readv_from_socket+0x25a/0x490 [cifs]
   ? __pfx_cifs_readv_from_socket+0x10/0x10 [cifs]
   ? srso_alias_return_thunk+0x5/0xfbef5
   cifs_read_from_socket+0xb5/0x100 [cifs]
   ? __pfx_cifs_read_from_socket+0x10/0x10 [cifs]
   ? __pfx_lock_release+0x10/0x10
   ? do_raw_spin_trylock+0xd1/0x120
   ? _raw_spin_unlock+0x23/0x40
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __smb2_find_mid+0x126/0x230 [cifs]
   cifs_demultiplex_thread+0xd39/0x1270 [cifs]
   ? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs]
   ? __pfx_lock_release+0x10/0x10
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? mark_held_locks+0x1a/0x90
   ? lockdep_hardirqs_on_prepare+0x136/0x210
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __kthread_parkme+0xce/0xf0
   ? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs]
   kthread+0x18d/0x1d0
   ? kthread+0xdb/0x1d0
   ? __pfx_kthread+0x10/0x10
   ret_from_fork+0x34/0x60
   ? __pfx_kthread+0x10/0x10
   ret_from_fork_asm+0x1b/0x30
   </TASK>

Fixes: 8ce79ec ("cifs: update multiplex loop to handle compounded responses")
Cc: [email protected]
Reported-by: Robert Morris <[email protected]>
Signed-off-by: Paulo Alcantara (SUSE) <[email protected]>
Signed-off-by: Steve French <[email protected]>
okias pushed a commit that referenced this pull request Dec 18, 2023
A small CIFS buffer (448 bytes) isn't big enough to hold
SMB2_QUERY_INFO request along with user's input data from
CIFS_QUERY_INFO ioctl.  That is, if the user passed an input buffer >
344 bytes, the client will memcpy() off the end of @req->Buffer in
SMB2_query_info_init() thus causing the following KASAN splat:

  BUG: KASAN: slab-out-of-bounds in SMB2_query_info_init+0x242/0x250 [cifs]
  Write of size 1023 at addr ffff88801308c5a8 by task a.out/1240

  CPU: 1 PID: 1240 Comm: a.out Not tainted 6.7.0-rc4 #5
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
  rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014
  Call Trace:
   <TASK>
   dump_stack_lvl+0x4a/0x80
   print_report+0xcf/0x650
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __phys_addr+0x46/0x90
   kasan_report+0xd8/0x110
   ? SMB2_query_info_init+0x242/0x250 [cifs]
   ? SMB2_query_info_init+0x242/0x250 [cifs]
   kasan_check_range+0x105/0x1b0
   __asan_memcpy+0x3c/0x60
   SMB2_query_info_init+0x242/0x250 [cifs]
   ? __pfx_SMB2_query_info_init+0x10/0x10 [cifs]
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? smb_rqst_len+0xa6/0xc0 [cifs]
   smb2_ioctl_query_info+0x4f4/0x9a0 [cifs]
   ? __pfx_smb2_ioctl_query_info+0x10/0x10 [cifs]
   ? __pfx_cifsConvertToUTF16+0x10/0x10 [cifs]
   ? kasan_set_track+0x25/0x30
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __kasan_kmalloc+0x8f/0xa0
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? cifs_strndup_to_utf16+0x12d/0x1a0 [cifs]
   ? __build_path_from_dentry_optional_prefix+0x19d/0x2d0 [cifs]
   ? __pfx_smb2_ioctl_query_info+0x10/0x10 [cifs]
   cifs_ioctl+0x11c7/0x1de0 [cifs]
   ? __pfx_cifs_ioctl+0x10/0x10 [cifs]
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? rcu_is_watching+0x23/0x50
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __rseq_handle_notify_resume+0x6cd/0x850
   ? __pfx___schedule+0x10/0x10
   ? blkcg_iostat_update+0x250/0x290
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? ksys_write+0xe9/0x170
   __x64_sys_ioctl+0xc9/0x100
   do_syscall_64+0x47/0xf0
   entry_SYSCALL_64_after_hwframe+0x6f/0x77
  RIP: 0033:0x7f893dde49cf
  Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48
  89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89>
  c2 3d 00 f0 ff ff 77 18 48 8b 44 24 18 64 48 2b 04 25 28 00 00
  RSP: 002b:00007ffc03ff4160 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  RAX: ffffffffffffffda RBX: 00007ffc03ff4378 RCX: 00007f893dde49cf
  RDX: 00007ffc03ff41d0 RSI: 00000000c018cf07 RDI: 0000000000000003
  RBP: 00007ffc03ff4260 R08: 0000000000000410 R09: 0000000000000001
  R10: 00007f893dce7300 R11: 0000000000000246 R12: 0000000000000000
  R13: 00007ffc03ff4388 R14: 00007f893df15000 R15: 0000000000406de0
   </TASK>

Fix this by increasing size of SMB2_QUERY_INFO request buffers and
validating input length to prevent other callers from overflowing @Req
in SMB2_query_info_init() as well.

Fixes: f5b05d6 ("cifs: add IOCTL for QUERY_INFO passthrough to userspace")
Cc: [email protected]
Reported-by: Robert Morris <[email protected]>
Signed-off-by: Paulo Alcantara <[email protected]>
Signed-off-by: Steve French <[email protected]>
okias pushed a commit that referenced this pull request Dec 19, 2023
Validate next header's offset in ->next_header() so that it isn't
smaller than MID_HEADER_SIZE(server) and then standard_receive3() or
->receive() ends up writing off the end of the buffer because
'pdu_length - MID_HEADER_SIZE(server)' wraps up to a huge length:

  BUG: KASAN: slab-out-of-bounds in _copy_to_iter+0x4fc/0x840
  Write of size 701 at addr ffff88800caf407f by task cifsd/1090

  CPU: 0 PID: 1090 Comm: cifsd Not tainted 6.7.0-rc4 #5
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
  rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014
  Call Trace:
   <TASK>
   dump_stack_lvl+0x4a/0x80
   print_report+0xcf/0x650
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __phys_addr+0x46/0x90
   kasan_report+0xd8/0x110
   ? _copy_to_iter+0x4fc/0x840
   ? _copy_to_iter+0x4fc/0x840
   kasan_check_range+0x105/0x1b0
   __asan_memcpy+0x3c/0x60
   _copy_to_iter+0x4fc/0x840
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? hlock_class+0x32/0xc0
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __pfx__copy_to_iter+0x10/0x10
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? lock_is_held_type+0x90/0x100
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __might_resched+0x278/0x360
   ? __pfx___might_resched+0x10/0x10
   ? srso_alias_return_thunk+0x5/0xfbef5
   __skb_datagram_iter+0x2c2/0x460
   ? __pfx_simple_copy_to_iter+0x10/0x10
   skb_copy_datagram_iter+0x6c/0x110
   tcp_recvmsg_locked+0x9be/0xf40
   ? __pfx_tcp_recvmsg_locked+0x10/0x10
   ? mark_held_locks+0x5d/0x90
   ? srso_alias_return_thunk+0x5/0xfbef5
   tcp_recvmsg+0xe2/0x310
   ? __pfx_tcp_recvmsg+0x10/0x10
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? lock_acquire+0x14a/0x3a0
   ? srso_alias_return_thunk+0x5/0xfbef5
   inet_recvmsg+0xd0/0x370
   ? __pfx_inet_recvmsg+0x10/0x10
   ? __pfx_lock_release+0x10/0x10
   ? do_raw_spin_trylock+0xd1/0x120
   sock_recvmsg+0x10d/0x150
   cifs_readv_from_socket+0x25a/0x490 [cifs]
   ? __pfx_cifs_readv_from_socket+0x10/0x10 [cifs]
   ? srso_alias_return_thunk+0x5/0xfbef5
   cifs_read_from_socket+0xb5/0x100 [cifs]
   ? __pfx_cifs_read_from_socket+0x10/0x10 [cifs]
   ? __pfx_lock_release+0x10/0x10
   ? do_raw_spin_trylock+0xd1/0x120
   ? _raw_spin_unlock+0x23/0x40
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __smb2_find_mid+0x126/0x230 [cifs]
   cifs_demultiplex_thread+0xd39/0x1270 [cifs]
   ? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs]
   ? __pfx_lock_release+0x10/0x10
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? mark_held_locks+0x1a/0x90
   ? lockdep_hardirqs_on_prepare+0x136/0x210
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __kthread_parkme+0xce/0xf0
   ? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs]
   kthread+0x18d/0x1d0
   ? kthread+0xdb/0x1d0
   ? __pfx_kthread+0x10/0x10
   ret_from_fork+0x34/0x60
   ? __pfx_kthread+0x10/0x10
   ret_from_fork_asm+0x1b/0x30
   </TASK>

Fixes: 8ce79ec ("cifs: update multiplex loop to handle compounded responses")
Cc: [email protected]
Reported-by: Robert Morris <[email protected]>
Signed-off-by: Paulo Alcantara (SUSE) <[email protected]>
Signed-off-by: Steve French <[email protected]>
okias pushed a commit that referenced this pull request Dec 19, 2023
A small CIFS buffer (448 bytes) isn't big enough to hold
SMB2_QUERY_INFO request along with user's input data from
CIFS_QUERY_INFO ioctl.  That is, if the user passed an input buffer >
344 bytes, the client will memcpy() off the end of @req->Buffer in
SMB2_query_info_init() thus causing the following KASAN splat:

  BUG: KASAN: slab-out-of-bounds in SMB2_query_info_init+0x242/0x250 [cifs]
  Write of size 1023 at addr ffff88801308c5a8 by task a.out/1240

  CPU: 1 PID: 1240 Comm: a.out Not tainted 6.7.0-rc4 #5
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
  rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014
  Call Trace:
   <TASK>
   dump_stack_lvl+0x4a/0x80
   print_report+0xcf/0x650
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __phys_addr+0x46/0x90
   kasan_report+0xd8/0x110
   ? SMB2_query_info_init+0x242/0x250 [cifs]
   ? SMB2_query_info_init+0x242/0x250 [cifs]
   kasan_check_range+0x105/0x1b0
   __asan_memcpy+0x3c/0x60
   SMB2_query_info_init+0x242/0x250 [cifs]
   ? __pfx_SMB2_query_info_init+0x10/0x10 [cifs]
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? smb_rqst_len+0xa6/0xc0 [cifs]
   smb2_ioctl_query_info+0x4f4/0x9a0 [cifs]
   ? __pfx_smb2_ioctl_query_info+0x10/0x10 [cifs]
   ? __pfx_cifsConvertToUTF16+0x10/0x10 [cifs]
   ? kasan_set_track+0x25/0x30
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __kasan_kmalloc+0x8f/0xa0
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? cifs_strndup_to_utf16+0x12d/0x1a0 [cifs]
   ? __build_path_from_dentry_optional_prefix+0x19d/0x2d0 [cifs]
   ? __pfx_smb2_ioctl_query_info+0x10/0x10 [cifs]
   cifs_ioctl+0x11c7/0x1de0 [cifs]
   ? __pfx_cifs_ioctl+0x10/0x10 [cifs]
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? rcu_is_watching+0x23/0x50
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __rseq_handle_notify_resume+0x6cd/0x850
   ? __pfx___schedule+0x10/0x10
   ? blkcg_iostat_update+0x250/0x290
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? ksys_write+0xe9/0x170
   __x64_sys_ioctl+0xc9/0x100
   do_syscall_64+0x47/0xf0
   entry_SYSCALL_64_after_hwframe+0x6f/0x77
  RIP: 0033:0x7f893dde49cf
  Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48
  89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89>
  c2 3d 00 f0 ff ff 77 18 48 8b 44 24 18 64 48 2b 04 25 28 00 00
  RSP: 002b:00007ffc03ff4160 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  RAX: ffffffffffffffda RBX: 00007ffc03ff4378 RCX: 00007f893dde49cf
  RDX: 00007ffc03ff41d0 RSI: 00000000c018cf07 RDI: 0000000000000003
  RBP: 00007ffc03ff4260 R08: 0000000000000410 R09: 0000000000000001
  R10: 00007f893dce7300 R11: 0000000000000246 R12: 0000000000000000
  R13: 00007ffc03ff4388 R14: 00007f893df15000 R15: 0000000000406de0
   </TASK>

Fix this by increasing size of SMB2_QUERY_INFO request buffers and
validating input length to prevent other callers from overflowing @Req
in SMB2_query_info_init() as well.

Fixes: f5b05d6 ("cifs: add IOCTL for QUERY_INFO passthrough to userspace")
Cc: [email protected]
Reported-by: Robert Morris <[email protected]>
Signed-off-by: Paulo Alcantara <[email protected]>
Signed-off-by: Steve French <[email protected]>
okias pushed a commit that referenced this pull request Dec 27, 2023
…@infineon.com

When sending an email to [email protected], the server
responds '550 #5.1.0 Address rejected.'

Signed-off-by: Lukas Bulwahn <[email protected]>
Signed-off-by: Kalle Valo <[email protected]>
Link: https://msgid.link/[email protected]
okias pushed a commit that referenced this pull request Dec 27, 2023
Jiri Pirko says:

====================
devlink: introduce notifications filtering

From: Jiri Pirko <[email protected]>

Currently the user listening on a socket for devlink notifications
gets always all messages for all existing devlink instances and objects,
even if he is interested only in one of those. That may cause
unnecessary overhead on setups with thousands of instances present.

User is currently able to narrow down the devlink objects replies
to dump commands by specifying select attributes.

Allow similar approach for notifications providing user a new
notify-filter-set command to select attributes with values
the notification message has to match. In that case, it is delivered
to the socket.

Note that the filtering is done per-socket, so multiple users may
specify different selection of attributes with values.

This patchset initially introduces support for following attributes:
DEVLINK_ATTR_BUS_NAME
DEVLINK_ATTR_DEV_NAME
DEVLINK_ATTR_PORT_INDEX

Patches #1 - #4 are preparations in devlink code, patch #3 is
                an optimization done on the way.
Patches #5 - #7 are preparations in netlink and generic netlink code.
Patch #8 is the main one in this set implementing of
         the notify-filter-set command and the actual
         per-socket filtering.
Patch grate-driver#9 extends the infrastructure allowing to filter according
         to a port index.

Example:
$ devlink mon port pci/0000:08:00.0/32768
[port,new] pci/0000:08:00.0/32768: type notset flavour pcisf controller 0 pfnum 0 sfnum 107 splittable false
  function:
    hw_addr 00:00:00:00:00:00 state inactive opstate detached roce enable
[port,new] pci/0000:08:00.0/32768: type eth flavour pcisf controller 0 pfnum 0 sfnum 107 splittable false
  function:
    hw_addr 00:00:00:00:00:00 state inactive opstate detached roce enable
[port,new] pci/0000:08:00.0/32768: type eth netdev eth3 flavour pcisf controller 0 pfnum 0 sfnum 107 splittable false
  function:
    hw_addr 00:00:00:00:00:00 state inactive opstate detached roce enable
[port,new] pci/0000:08:00.0/32768: type eth netdev eth3 flavour pcisf controller 0 pfnum 0 sfnum 107 splittable false
  function:
    hw_addr 00:00:00:00:00:00 state inactive opstate detached roce enable
[port,new] pci/0000:08:00.0/32768: type eth flavour pcisf controller 0 pfnum 0 sfnum 107 splittable false
  function:
    hw_addr 00:00:00:00:00:00 state inactive opstate detached roce enable
[port,new] pci/0000:08:00.0/32768: type notset flavour pcisf controller 0 pfnum 0 sfnum 107 splittable false
  function:
    hw_addr 00:00:00:00:00:00 state inactive opstate detached roce enable
[port,del] pci/0000:08:00.0/32768: type notset flavour pcisf controller 0 pfnum 0 sfnum 107 splittable false
  function:
    hw_addr 00:00:00:00:00:00 state inactive opstate detached roce enable
====================

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Paolo Abeni <[email protected]>
okias pushed a commit that referenced this pull request Dec 27, 2023
Andrii Nakryiko says:

====================
Enhance BPF global subprogs with argument tags

This patch set adds verifier support for annotating user's global BPF subprog
arguments with few commonly requested annotations, to improve global subprog
verification experience.

These tags are:
  - ability to annotate a special PTR_TO_CTX argument;
  - ability to annotate a generic PTR_TO_MEM as non-null.

We utilize btf_decl_tag attribute for this and provide two helper macros as
part of bpf_helpers.h in libbpf (patch #8).

Besides this we also add abilit to pass a pointer to dynptr into global
subprog. This is done based on type name match (struct bpf_dynptr *). This
allows to pass dynptrs into global subprogs, for use cases that deal with
variable-sized generic memory pointers.

Big chunk of the patch set (patches #1 through #5) are various refactorings to
make verifier internals around global subprog validation logic easier to
extend and support long term, eliminating BTF parsing logic duplication,
factoring out argument expectation definitions from BTF parsing, etc.

New functionality is added in patch #6 (ctx and non-null) and patch #7
(dynptr), extending global subprog checks with awareness for arg tags.

Patch grate-driver#9 adds simple tests validating each of the added tags and dynptr
argument passing.

Patch grate-driver#10 adds a simple negative case for freplace programs to make sure that
target BPF programs with "unreliable" BTF func proto cannot be freplaced.

v2->v3:
  - patch grate-driver#10 improved by checking expected verifier error (Eduard);
v1->v2:
  - dropped packet args for now (Eduard);
  - added back unreliable=true detection for entry BPF programs (Eduard);
  - improved subprog arg validation (Eduard);
  - switched dynptr arg from tag to just type name based check (Eduard).
====================

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>
okias pushed a commit that referenced this pull request Dec 27, 2023
Ido Schimmel says:

====================
Add MDB bulk deletion support

This patchset adds MDB bulk deletion support, allowing user space to
request the deletion of matching entries instead of dumping the entire
MDB and issuing a separate deletion request for each matching entry.
Support is added in both the bridge and VXLAN drivers in a similar
fashion to the existing FDB bulk deletion support.

The parameters according to which bulk deletion can be performed are
similar to the FDB ones, namely: Destination port, VLAN ID, state (e.g.,
"permanent"), routing protocol, source / destination VNI, destination IP
and UDP port. Flushing based on flags (e.g., "offload", "fast_leave",
"added_by_star_ex", "blocked") is not currently supported, but can be
added in the future, if a use case arises.

Patch #1 adds a new uAPI attribute to allow specifying the state mask
according to which bulk deletion will be performed, if any.

Patch #2 adds a new policy according to which bulk deletion requests
(with 'NLM_F_BULK' flag set) will be parsed.

Patches #3-#4 add a new NDO for MDB bulk deletion and invoke it from the
rtnetlink code when a bulk deletion request is made.

Patches #5-#6 implement the MDB bulk deletion NDO in the bridge and
VXLAN drivers, respectively.

Patch #7 allows user space to issue MDB bulk deletion requests by no
longer rejecting the 'NLM_F_BULK' flag when it is set in 'RTM_DELMDB'
requests.

Patches #8-grate-driver#9 add selftests for both drivers, for both good and bad
flows.

iproute2 changes can be found here [1].

https://github.com/idosch/iproute2/tree/submit/mdb_flush_v1
====================

Signed-off-by: David S. Miller <[email protected]>
okias pushed a commit that referenced this pull request Dec 27, 2023
Trying to suspend to RAM on SAMA5D27 EVK leads to the following lockdep
warning:

 ============================================
 WARNING: possible recursive locking detected
 6.7.0-rc5-wt+ #532 Not tainted
 --------------------------------------------
 sh/92 is trying to acquire lock:
 c3cf306c (&irq_desc_lock_class){-.-.}-{2:2}, at: __irq_get_desc_lock+0xe8/0x100

 but task is already holding lock:
 c3d7c46c (&irq_desc_lock_class){-.-.}-{2:2}, at: __irq_get_desc_lock+0xe8/0x100

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

        CPU0
        ----
   lock(&irq_desc_lock_class);
   lock(&irq_desc_lock_class);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 6 locks held by sh/92:
  #0: c3aa0258 (sb_writers#6){.+.+}-{0:0}, at: ksys_write+0xd8/0x178
  #1: c4c2df44 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x138/0x284
  #2: c32684a0 (kn->active){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x148/0x284
  #3: c232b6d4 (system_transition_mutex){+.+.}-{3:3}, at: pm_suspend+0x13c/0x4e8
  #4: c387b088 (&dev->mutex){....}-{3:3}, at: __device_suspend+0x1e8/0x91c
  #5: c3d7c46c (&irq_desc_lock_class){-.-.}-{2:2}, at: __irq_get_desc_lock+0xe8/0x100

 stack backtrace:
 CPU: 0 PID: 92 Comm: sh Not tainted 6.7.0-rc5-wt+ #532
 Hardware name: Atmel SAMA5
  unwind_backtrace from show_stack+0x18/0x1c
  show_stack from dump_stack_lvl+0x34/0x48
  dump_stack_lvl from __lock_acquire+0x19ec/0x3a0c
  __lock_acquire from lock_acquire.part.0+0x124/0x2d0
  lock_acquire.part.0 from _raw_spin_lock_irqsave+0x5c/0x78
  _raw_spin_lock_irqsave from __irq_get_desc_lock+0xe8/0x100
  __irq_get_desc_lock from irq_set_irq_wake+0xa8/0x204
  irq_set_irq_wake from atmel_gpio_irq_set_wake+0x58/0xb4
  atmel_gpio_irq_set_wake from irq_set_irq_wake+0x100/0x204
  irq_set_irq_wake from gpio_keys_suspend+0xec/0x2b8
  gpio_keys_suspend from dpm_run_callback+0xe4/0x248
  dpm_run_callback from __device_suspend+0x234/0x91c
  __device_suspend from dpm_suspend+0x224/0x43c
  dpm_suspend from dpm_suspend_start+0x9c/0xa8
  dpm_suspend_start from suspend_devices_and_enter+0x1e0/0xa84
  suspend_devices_and_enter from pm_suspend+0x460/0x4e8
  pm_suspend from state_store+0x78/0xe4
  state_store from kernfs_fop_write_iter+0x1a0/0x284
  kernfs_fop_write_iter from vfs_write+0x38c/0x6f4
  vfs_write from ksys_write+0xd8/0x178
  ksys_write from ret_fast_syscall+0x0/0x1c
 Exception stack(0xc52b3fa8 to 0xc52b3ff0)
 3fa0:                   00000004 005a0ae8 00000001 005a0ae8 00000004 00000001
 3fc0: 00000004 005a0ae8 00000001 00000004 00000004 b6c616c0 00000020 0059d190
 3fe0: 00000004 b6c61678 aec5a041 aebf1a26

This warning is raised because pinctrl-at91-pio4 uses chained IRQ. Whenever
a wake up source configures an IRQ through irq_set_irq_wake, it will
lock the corresponding IRQ desc, and then call irq_set_irq_wake on "parent"
IRQ which will do the same on its own IRQ desc, but since those two locks
share the same class, lockdep reports this as an issue.

Fix lockdep false positive by setting a different class for parent and
children IRQ

Fixes: 7761808 ("pinctrl: introduce driver for Atmel PIO4 controller")
Signed-off-by: Alexis Lothoré <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Linus Walleij <[email protected]>
okias pushed a commit that referenced this pull request Dec 27, 2023
An issue occurred while reading an ELF file in libbpf.c during fuzzing:

	Program received signal SIGSEGV, Segmentation fault.
	0x0000000000958e97 in bpf_object.collect_prog_relos () at libbpf.c:4206
	4206 in libbpf.c
	(gdb) bt
	#0 0x0000000000958e97 in bpf_object.collect_prog_relos () at libbpf.c:4206
	#1 0x000000000094f9d6 in bpf_object.collect_relos () at libbpf.c:6706
	#2 0x000000000092bef3 in bpf_object_open () at libbpf.c:7437
	#3 0x000000000092c046 in bpf_object.open_mem () at libbpf.c:7497
	#4 0x0000000000924afa in LLVMFuzzerTestOneInput () at fuzz/bpf-object-fuzzer.c:16
	#5 0x000000000060be11 in testblitz_engine::fuzzer::Fuzzer::run_one ()
	#6 0x000000000087ad92 in tracing::span::Span::in_scope ()
	#7 0x00000000006078aa in testblitz_engine::fuzzer::util::walkdir ()
	#8 0x00000000005f3217 in testblitz_engine::entrypoint::main::{{closure}} ()
	grate-driver#9 0x00000000005f2601 in main ()
	(gdb)

scn_data was null at this code(tools/lib/bpf/src/libbpf.c):

	if (rel->r_offset % BPF_INSN_SZ || rel->r_offset >= scn_data->d_size) {

The scn_data is derived from the code above:

	scn = elf_sec_by_idx(obj, sec_idx);
	scn_data = elf_sec_data(obj, scn);

	relo_sec_name = elf_sec_str(obj, shdr->sh_name);
	sec_name = elf_sec_name(obj, scn);
	if (!relo_sec_name || !sec_name)// don't check whether scn_data is NULL
		return -EINVAL;

In certain special scenarios, such as reading a malformed ELF file,
it is possible that scn_data may be a null pointer

Signed-off-by: Mingyi Zhang <[email protected]>
Signed-off-by: Xin Liu <[email protected]>
Signed-off-by: Changye Wu <[email protected]>
Signed-off-by: Andrii Nakryiko <[email protected]>
Signed-off-by: Daniel Borkmann <[email protected]>
Acked-by: Daniel Borkmann <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]
okias pushed a commit that referenced this pull request Jan 7, 2024
[ Upstream commit a84fbf2 ]

Generating metrics llc_code_read_mpi_demand_plus_prefetch,
llc_data_read_mpi_demand_plus_prefetch,
llc_miss_local_memory_bandwidth_read,
llc_miss_local_memory_bandwidth_write,
nllc_miss_remote_memory_bandwidth_read, memory_bandwidth_read,
memory_bandwidth_write, uncore_frequency, upi_data_transmit_bw,
C2_Pkg_Residency, C3_Core_Residency, C3_Pkg_Residency,
C6_Core_Residency, C6_Pkg_Residency, C7_Core_Residency,
C7_Pkg_Residency, UNCORE_FREQ and tma_info_system_socket_clks would
trigger an address sanitizer heap-buffer-overflows on a SkylakeX.

```
==2567752==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x5020003ed098 at pc 0x5621a816654e bp 0x7fffb55d4da0 sp 0x7fffb55d4d98
READ of size 4 at 0x5020003eee78 thread T0
    #0 0x558265d6654d in aggr_cpu_id__is_empty tools/perf/util/cpumap.c:694:12
    #1 0x558265c914da in perf_stat__get_aggr tools/perf/builtin-stat.c:1490:6
    #2 0x558265c914da in perf_stat__get_global_cached tools/perf/builtin-stat.c:1530:9
    #3 0x558265e53290 in should_skip_zero_counter tools/perf/util/stat-display.c:947:31
    #4 0x558265e53290 in print_counter_aggrdata tools/perf/util/stat-display.c:985:18
    #5 0x558265e51931 in print_counter tools/perf/util/stat-display.c:1110:3
    #6 0x558265e51931 in evlist__print_counters tools/perf/util/stat-display.c:1571:5
    #7 0x558265c8ec87 in print_counters tools/perf/builtin-stat.c:981:2
    #8 0x558265c8cc71 in cmd_stat tools/perf/builtin-stat.c:2837:3
    grate-driver#9 0x558265bb9bd4 in run_builtin tools/perf/perf.c:323:11
    grate-driver#10 0x558265bb98eb in handle_internal_command tools/perf/perf.c:377:8
    grate-driver#11 0x558265bb9389 in run_argv tools/perf/perf.c:421:2
    grate-driver#12 0x558265bb9389 in main tools/perf/perf.c:537:3
```

The issue was the use of testing a cpumap with NULL rather than using
empty, as a map containing the dummy value isn't NULL and the -1
results in an empty aggr map being allocated which legitimately
overflows when any member is accessed.

Fixes: 8a96f45 ("perf stat: Avoid SEGV if core.cpus isn't set")
Signed-off-by: Ian Rogers <[email protected]>
Acked-by: Namhyung Kim <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
okias pushed a commit that referenced this pull request Jan 7, 2024
[ Upstream commit ede72dc ]

Fuzzing found that an invalid tracepoint name would create a memory
leak with an address sanitizer build:
```
$ perf stat -e '*:o/' true
event syntax error: '*:o/'
                       \___ parser error
Run 'perf list' for a list of valid events

 Usage: perf stat [<options>] [<command>]

    -e, --event <event>   event selector. use 'perf list' to list available events

=================================================================
==59380==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 4 byte(s) in 2 object(s) allocated from:
    #0 0x7f38ac07077b in __interceptor_strdup ../../../../src/libsanitizer/asan/asan_interceptors.cpp:439
    #1 0x55f2f41be73b in str util/parse-events.l:49
    #2 0x55f2f41d08e8 in parse_events_lex util/parse-events.l:338
    #3 0x55f2f41dc3b1 in parse_events_parse util/parse-events-bison.c:1464
    #4 0x55f2f410b8b3 in parse_events__scanner util/parse-events.c:1822
    #5 0x55f2f410d1b9 in __parse_events util/parse-events.c:2094
    #6 0x55f2f410e57f in parse_events_option util/parse-events.c:2279
    #7 0x55f2f4427b56 in get_value tools/lib/subcmd/parse-options.c:251
    #8 0x55f2f4428d98 in parse_short_opt tools/lib/subcmd/parse-options.c:351
    grate-driver#9 0x55f2f4429d80 in parse_options_step tools/lib/subcmd/parse-options.c:539
    grate-driver#10 0x55f2f442acb9 in parse_options_subcommand tools/lib/subcmd/parse-options.c:654
    grate-driver#11 0x55f2f3ec99fc in cmd_stat tools/perf/builtin-stat.c:2501
    grate-driver#12 0x55f2f4093289 in run_builtin tools/perf/perf.c:322
    grate-driver#13 0x55f2f40937f5 in handle_internal_command tools/perf/perf.c:375
    grate-driver#14 0x55f2f4093bbd in run_argv tools/perf/perf.c:419
    grate-driver#15 0x55f2f409412b in main tools/perf/perf.c:535

SUMMARY: AddressSanitizer: 4 byte(s) leaked in 2 allocation(s).
```
Fix by adding the missing destructor.

Fixes: 865582c ("perf tools: Adds the tracepoint name parsing support")
Signed-off-by: Ian Rogers <[email protected]>
Cc: He Kuang <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Namhyung Kim <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
okias pushed a commit that referenced this pull request Jan 7, 2024
commit d8b90d6 upstream.

When scanning namespaces, it is possible to get valid data from the first
call to nvme_identify_ns() in nvme_alloc_ns(), but not from the second
call in nvme_update_ns_info_block().  In particular, if the NSID becomes
inactive between the two commands, a storage device may return a buffer
filled with zero as per 4.1.5.1.  In this case, we can get a kernel crash
due to a divide-by-zero in blk_stack_limits() because ns->lba_shift will
be set to zero.

PID: 326      TASK: ffff95fec3cd8000  CPU: 29   COMMAND: "kworker/u98:10"
 #0 [ffffad8f8702f9e0] machine_kexec at ffffffff91c76ec7
 #1 [ffffad8f8702fa38] __crash_kexec at ffffffff91dea4fa
 #2 [ffffad8f8702faf8] crash_kexec at ffffffff91deb788
 #3 [ffffad8f8702fb00] oops_end at ffffffff91c2e4bb
 #4 [ffffad8f8702fb20] do_trap at ffffffff91c2a4ce
 #5 [ffffad8f8702fb70] do_error_trap at ffffffff91c2a595
 #6 [ffffad8f8702fbb0] exc_divide_error at ffffffff928506e6
 #7 [ffffad8f8702fbd0] asm_exc_divide_error at ffffffff92a00926
    [exception RIP: blk_stack_limits+434]
    RIP: ffffffff92191872  RSP: ffffad8f8702fc80  RFLAGS: 00010246
    RAX: 0000000000000000  RBX: ffff95efa0c91800  RCX: 0000000000000001
    RDX: 0000000000000000  RSI: 0000000000000001  RDI: 0000000000000001
    RBP: 00000000ffffffff   R8: ffff95fec7df35a8   R9: 0000000000000000
    R10: 0000000000000000  R11: 0000000000000001  R12: 0000000000000000
    R13: 0000000000000000  R14: 0000000000000000  R15: ffff95fed33c09a8
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #8 [ffffad8f8702fce0] nvme_update_ns_info_block at ffffffffc06d3533 [nvme_core]
 grate-driver#9 [ffffad8f8702fd18] nvme_scan_ns at ffffffffc06d6fa7 [nvme_core]

This happened when the check for valid data was moved out of nvme_identify_ns()
into one of the callers.  Fix this by checking in both callers.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=218186
Fixes: 0dd6fff ("nvme: bring back auto-removal of deleted namespaces during sequential scan")
Cc: [email protected]
Signed-off-by: Ewan D. Milne <[email protected]>
Signed-off-by: Keith Busch <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
okias pushed a commit that referenced this pull request Jan 7, 2024
[ Upstream commit e3e82fc ]

When creating ceq_0 during probing irdma, cqp.sc_cqp will be sent as a
cqp_request to cqp->sc_cqp.sq_ring. If the request is pending when
removing the irdma driver or unplugging its aux device, cqp.sc_cqp will be
dereferenced as wrong struct in irdma_free_pending_cqp_request().

  PID: 3669   TASK: ffff88aef892c000  CPU: 28  COMMAND: "kworker/28:0"
   #0 [fffffe0000549e38] crash_nmi_callback at ffffffff810e3a34
   #1 [fffffe0000549e40] nmi_handle at ffffffff810788b2
   #2 [fffffe0000549ea0] default_do_nmi at ffffffff8107938f
   #3 [fffffe0000549eb8] do_nmi at ffffffff81079582
   #4 [fffffe0000549ef0] end_repeat_nmi at ffffffff82e016b4
      [exception RIP: native_queued_spin_lock_slowpath+1291]
      RIP: ffffffff8127e72b  RSP: ffff88aa841ef778  RFLAGS: 00000046
      RAX: 0000000000000000  RBX: ffff88b01f849700  RCX: ffffffff8127e47e
      RDX: 0000000000000000  RSI: 0000000000000004  RDI: ffffffff83857ec0
      RBP: ffff88afe3e4efc8   R8: ffffed15fc7c9dfa   R9: ffffed15fc7c9dfa
      R10: 0000000000000001  R11: ffffed15fc7c9df9  R12: 0000000000740000
      R13: ffff88b01f849708  R14: 0000000000000003  R15: ffffed1603f092e1
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0000
  -- <NMI exception stack> --
   #5 [ffff88aa841ef778] native_queued_spin_lock_slowpath at ffffffff8127e72b
   #6 [ffff88aa841ef7b0] _raw_spin_lock_irqsave at ffffffff82c22aa4
   #7 [ffff88aa841ef7c8] __wake_up_common_lock at ffffffff81257363
   #8 [ffff88aa841ef888] irdma_free_pending_cqp_request at ffffffffa0ba12cc [irdma]
   grate-driver#9 [ffff88aa841ef958] irdma_cleanup_pending_cqp_op at ffffffffa0ba1469 [irdma]
   grate-driver#10 [ffff88aa841ef9c0] irdma_ctrl_deinit_hw at ffffffffa0b2989f [irdma]
   grate-driver#11 [ffff88aa841efa28] irdma_remove at ffffffffa0b252df [irdma]
   grate-driver#12 [ffff88aa841efae8] auxiliary_bus_remove at ffffffff8219afdb
   grate-driver#13 [ffff88aa841efb00] device_release_driver_internal at ffffffff821882e6
   grate-driver#14 [ffff88aa841efb38] bus_remove_device at ffffffff82184278
   grate-driver#15 [ffff88aa841efb88] device_del at ffffffff82179d23
   grate-driver#16 [ffff88aa841efc48] ice_unplug_aux_dev at ffffffffa0eb1c14 [ice]
   grate-driver#17 [ffff88aa841efc68] ice_service_task at ffffffffa0d88201 [ice]
   grate-driver#18 [ffff88aa841efde8] process_one_work at ffffffff811c589a
   grate-driver#19 [ffff88aa841efe60] worker_thread at ffffffff811c71ff
   grate-driver#20 [ffff88aa841eff10] kthread at ffffffff811d87a0
   grate-driver#21 [ffff88aa841eff50] ret_from_fork at ffffffff82e0022f

Fixes: 44d9e52 ("RDMA/irdma: Implement device initialization definitions")
Link: https://lore.kernel.org/r/[email protected]
Suggested-by: "Ismail, Mustafa" <[email protected]>
Signed-off-by: Shifeng Li <[email protected]>
Reviewed-by: Shiraz Saleem <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
okias pushed a commit that referenced this pull request Jan 7, 2024
commit fe2b122 upstream.

When working on LED support for r8169 I got the following lockdep
warning. Easiest way to prevent this scenario seems to be to take
the RTNL lock before the trigger_data lock in set_device_name().

======================================================
WARNING: possible circular locking dependency detected
6.7.0-rc2-next-20231124+ #2 Not tainted
------------------------------------------------------
bash/383 is trying to acquire lock:
ffff888103aa1c68 (&trigger_data->lock){+.+.}-{3:3}, at: netdev_trig_notify+0xec/0x190 [ledtrig_netdev]

but task is already holding lock:
ffffffff8cddf808 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x12/0x20

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (rtnl_mutex){+.+.}-{3:3}:
       __mutex_lock+0x9b/0xb50
       mutex_lock_nested+0x16/0x20
       rtnl_lock+0x12/0x20
       set_device_name+0xa9/0x120 [ledtrig_netdev]
       netdev_trig_activate+0x1a1/0x230 [ledtrig_netdev]
       led_trigger_set+0x172/0x2c0
       led_trigger_write+0xf1/0x140
       sysfs_kf_bin_write+0x5d/0x80
       kernfs_fop_write_iter+0x15d/0x210
       vfs_write+0x1f0/0x510
       ksys_write+0x6c/0xf0
       __x64_sys_write+0x14/0x20
       do_syscall_64+0x3f/0xf0
       entry_SYSCALL_64_after_hwframe+0x6c/0x74

-> #0 (&trigger_data->lock){+.+.}-{3:3}:
       __lock_acquire+0x1459/0x25a0
       lock_acquire+0xc8/0x2d0
       __mutex_lock+0x9b/0xb50
       mutex_lock_nested+0x16/0x20
       netdev_trig_notify+0xec/0x190 [ledtrig_netdev]
       call_netdevice_register_net_notifiers+0x5a/0x100
       register_netdevice_notifier+0x85/0x120
       netdev_trig_activate+0x1d4/0x230 [ledtrig_netdev]
       led_trigger_set+0x172/0x2c0
       led_trigger_write+0xf1/0x140
       sysfs_kf_bin_write+0x5d/0x80
       kernfs_fop_write_iter+0x15d/0x210
       vfs_write+0x1f0/0x510
       ksys_write+0x6c/0xf0
       __x64_sys_write+0x14/0x20
       do_syscall_64+0x3f/0xf0
       entry_SYSCALL_64_after_hwframe+0x6c/0x74

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(rtnl_mutex);
                               lock(&trigger_data->lock);
                               lock(rtnl_mutex);
  lock(&trigger_data->lock);

 *** DEADLOCK ***

8 locks held by bash/383:
 #0: ffff888103ff33f0 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x6c/0xf0
 #1: ffff888103aa1e88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x114/0x210
 #2: ffff8881036f1890 (kn->active#82){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x11d/0x210
 #3: ffff888108e2c358 (&led_cdev->led_access){+.+.}-{3:3}, at: led_trigger_write+0x30/0x140
 #4: ffffffff8cdd9e10 (triggers_list_lock){++++}-{3:3}, at: led_trigger_write+0x75/0x140
 #5: ffff888108e2c270 (&led_cdev->trigger_lock){++++}-{3:3}, at: led_trigger_write+0xe3/0x140
 #6: ffffffff8cdde3d0 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1c/0x120
 #7: ffffffff8cddf808 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x12/0x20

stack backtrace:
CPU: 0 PID: 383 Comm: bash Not tainted 6.7.0-rc2-next-20231124+ #2
Hardware name: Default string Default string/Default string, BIOS ADLN.M6.SODIMM.ZB.CY.015 08/08/2023
Call Trace:
 <TASK>
 dump_stack_lvl+0x5c/0xd0
 dump_stack+0x10/0x20
 print_circular_bug+0x2dd/0x410
 check_noncircular+0x131/0x150
 __lock_acquire+0x1459/0x25a0
 lock_acquire+0xc8/0x2d0
 ? netdev_trig_notify+0xec/0x190 [ledtrig_netdev]
 __mutex_lock+0x9b/0xb50
 ? netdev_trig_notify+0xec/0x190 [ledtrig_netdev]
 ? __this_cpu_preempt_check+0x13/0x20
 ? netdev_trig_notify+0xec/0x190 [ledtrig_netdev]
 ? __cancel_work_timer+0x11c/0x1b0
 ? __mutex_lock+0x123/0xb50
 mutex_lock_nested+0x16/0x20
 ? mutex_lock_nested+0x16/0x20
 netdev_trig_notify+0xec/0x190 [ledtrig_netdev]
 call_netdevice_register_net_notifiers+0x5a/0x100
 register_netdevice_notifier+0x85/0x120
 netdev_trig_activate+0x1d4/0x230 [ledtrig_netdev]
 led_trigger_set+0x172/0x2c0
 ? preempt_count_add+0x49/0xc0
 led_trigger_write+0xf1/0x140
 sysfs_kf_bin_write+0x5d/0x80
 kernfs_fop_write_iter+0x15d/0x210
 vfs_write+0x1f0/0x510
 ksys_write+0x6c/0xf0
 __x64_sys_write+0x14/0x20
 do_syscall_64+0x3f/0xf0
 entry_SYSCALL_64_after_hwframe+0x6c/0x74
RIP: 0033:0x7f269055d034
Code: c7 00 16 00 00 00 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 80 3d 35 c3 0d 00 00 74 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 48 83 ec 28 48 89 54 24 18 48
RSP: 002b:00007ffddb7ef748 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 00007f269055d034
RDX: 0000000000000007 RSI: 000055bf5f4af3c0 RDI: 0000000000000001
RBP: 000055bf5f4af3c0 R08: 0000000000000073 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000007
R13: 00007f26906325c0 R14: 00007f269062ff20 R15: 0000000000000000
 </TASK>

Fixes: d5e0126 ("leds: trigger: netdev: add additional specific link speed mode")
Cc: [email protected]
Signed-off-by: Heiner Kallweit <[email protected]>
Reviewed-by: Andrew Lunn <[email protected]>
Acked-by: Lee Jones <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
okias pushed a commit that referenced this pull request Jan 11, 2024
bpf_cgroup_from_id() is basically a wrapper to cgroup_get_from_id(),
that is relying on kernfs to determine the right cgroup associated to
the target id.

As a kfunc, it has the potential to be attached to any function through
BPF, particularly in contexts where certain locks are held.

However, kernfs is not using an irq safe spinlock for kernfs_idr_lock,
that means any kernfs function that is acquiring this lock can be
interrupted and potentially hit bpf_cgroup_from_id() in the process,
triggering a deadlock.

For example, it is really easy to trigger a lockdep splat between
kernfs_idr_lock and rq->_lock, attaching a small BPF program to
__set_cpus_allowed_ptr_locked() that just calls bpf_cgroup_from_id():

 =====================================================
 WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected
 6.7.0-rc7-virtme #5 Not tainted
 -----------------------------------------------------
 repro/131 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
 ffffffffb2dc4578 (kernfs_idr_lock){+.+.}-{2:2}, at: kernfs_find_and_get_node_by_id+0x1d/0x80

 and this task is already holding:
 ffff911cbecaf218 (&rq->__lock){-.-.}-{2:2}, at: task_rq_lock+0x50/0xc0
 which would create a new lock dependency:
  (&rq->__lock){-.-.}-{2:2} -> (kernfs_idr_lock){+.+.}-{2:2}

 but this new dependency connects a HARDIRQ-irq-safe lock:
  (&rq->__lock){-.-.}-{2:2}

 ... which became HARDIRQ-irq-safe at:
   lock_acquire+0xbf/0x2b0
   _raw_spin_lock_nested+0x2e/0x40
   scheduler_tick+0x5d/0x170
   update_process_times+0x9c/0xb0
   tick_periodic+0x27/0xe0
   tick_handle_periodic+0x24/0x70
   __sysvec_apic_timer_interrupt+0x64/0x1a0
   sysvec_apic_timer_interrupt+0x6f/0x80
   asm_sysvec_apic_timer_interrupt+0x1a/0x20
   memcpy+0xc/0x20
   arch_dup_task_struct+0x15/0x30
   copy_process+0x1ce/0x1eb0
   kernel_clone+0xac/0x390
   kernel_thread+0x6f/0xa0
   kthreadd+0x199/0x230
   ret_from_fork+0x31/0x50
   ret_from_fork_asm+0x1b/0x30

 to a HARDIRQ-irq-unsafe lock:
  (kernfs_idr_lock){+.+.}-{2:2}

 ... which became HARDIRQ-irq-unsafe at:
 ...
   lock_acquire+0xbf/0x2b0
   _raw_spin_lock+0x30/0x40
   __kernfs_new_node.isra.0+0x83/0x280
   kernfs_create_root+0xf6/0x1d0
   sysfs_init+0x1b/0x70
   mnt_init+0xd9/0x2a0
   vfs_caches_init+0xcf/0xe0
   start_kernel+0x58a/0x6a0
   x86_64_start_reservations+0x18/0x30
   x86_64_start_kernel+0xc5/0xe0
   secondary_startup_64_no_verify+0x178/0x17b

 other info that might help us debug this:

  Possible interrupt unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(kernfs_idr_lock);
                                local_irq_disable();
                                lock(&rq->__lock);
                                lock(kernfs_idr_lock);
   <Interrupt>
     lock(&rq->__lock);

  *** DEADLOCK ***

Prevent this deadlock condition converting kernfs_idr_lock to a raw irq
safe spinlock.

The performance impact of this change should be negligible and it also
helps to prevent similar deadlock conditions with any other subsystems
that may depend on kernfs.

Fixes: 332ea1f ("bpf: Add bpf_cgroup_from_id() kfunc")
Cc: stable <[email protected]>
Signed-off-by: Andrea Righi <[email protected]>
Acked-by: Tejun Heo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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