[moderation] [fs?] KCSAN: data-race in has_bh_in_lru / invalidate_bh_lrus_cpu (9)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 9d1694dc91ce Merge tag 'for-6.8/block-2024-01-18' of git:/..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=140fe407e80000
kernel config: https://syzkaller.appspot.com/x/.config?x=afe76ef1b82444cf
dashboard link: https://syzkaller.appspot.com/bug?extid=60f8f932634d21750e8a
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [bra...@kernel.org ja...@suse.cz linux-...@vger.kernel.org linux-...@vger.kernel.org vi...@zeniv.linux.org.uk]

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/ca73a5ac6e74/disk-9d1694dc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/d599970abc9b/vmlinux-9d1694dc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ed9beb079aaf/bzImage-9d1694dc.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+60f8f9...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in has_bh_in_lru / invalidate_bh_lrus_cpu

write to 0xffff888237c2a710 of 8 bytes by task 27046 on cpu 0:
__invalidate_bh_lrus fs/buffer.c:1488 [inline]
invalidate_bh_lrus_cpu+0x82/0xb0 fs/buffer.c:1533
lru_add_and_bh_lrus_drain mm/swap.c:768 [inline]
lru_add_drain_per_cpu+0x70/0x90 mm/swap.c:787
process_one_work kernel/workqueue.c:2633 [inline]
process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2706
worker_thread+0x525/0x730 kernel/workqueue.c:2787
kthread+0x1d7/0x210 kernel/kthread.c:388
ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

read to 0xffff888237c2a710 of 8 bytes by task 8862 on cpu 1:
has_bh_in_lru+0x35/0x1e0 fs/buffer.c:1510
smp_call_function_many_cond+0x2e4/0xc20 kernel/smp.c:808
on_each_cpu_cond_mask+0x3c/0x80 kernel/smp.c:1023
on_each_cpu_cond include/linux/smp.h:105 [inline]
invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1519
invalidate_bdev block/bdev.c:88 [inline]
bdev_mark_dead+0xe4/0x110 block/bdev.c:1057
disk_force_media_change+0xb6/0xe0 block/disk-events.c:298
__loop_clr_fd+0x242/0x3a0 drivers/block/loop.c:1170
loop_clr_fd drivers/block/loop.c:1253 [inline]
lo_ioctl+0xe93/0x12e0 drivers/block/loop.c:1557
blkdev_ioctl+0x375/0x460 block/ioctl.c:636
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl+0xcf/0x140 fs/ioctl.c:857
__x64_sys_ioctl+0x43/0x50 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x59/0x120 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0xffff8881068296e8 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 8862 Comm: syz-executor.5 Not tainted 6.7.0-syzkaller-12377-g9d1694dc91ce #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
==================================================================


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.