[moderation] [kernel?] KCSAN: data-race in process_scheduled_works / process_scheduled_works

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 9ace34a8e446 Merge tag 'cgroup-for-6.7-rc4-fixes' of git:/..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10affe0ee80000
kernel config: https://syzkaller.appspot.com/x/.config?x=ac34c1f29a8029df
dashboard link: https://syzkaller.appspot.com/bug?extid=0a915df4b14b87cab72e
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [b...@alien8.de dave....@linux.intel.com h...@zytor.com linux-...@vger.kernel.org mi...@redhat.com tg...@linutronix.de x...@kernel.org]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/955528ed37c5/disk-9ace34a8.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ed03c0892611/vmlinux-9ace34a8.xz
kernel image: https://storage.googleapis.com/syzbot-assets/b4d56563956a/bzImage-9ace34a8.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0a915d...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in process_scheduled_works / process_scheduled_works

read-write to 0xffff8881000670a0 of 8 bytes by task 26 on cpu 0:
process_one_work kernel/workqueue.c:2633 [inline]
process_scheduled_works+0x5e3/0xa30 kernel/workqueue.c:2700
worker_thread+0x525/0x730 kernel/workqueue.c:2781
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-write to 0xffff8881000670a0 of 8 bytes by task 1576 on cpu 1:
process_one_work kernel/workqueue.c:2633 [inline]
process_scheduled_works+0x5e3/0xa30 kernel/workqueue.c:2700
worker_thread+0x525/0x730 kernel/workqueue.c:2781
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

value changed: 0x00000000000003e7 -> 0x00000000000003e8

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 1576 Comm: kworker/u4:5 Not tainted 6.7.0-rc4-syzkaller-00039-g9ace34a8e446 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Workqueue: events_unbound fsnotify_connector_destroy_workfn
==================================================================


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