syzbot

==================================================================
BUG: KCSAN: data-race in wb_wait_for_completion / writeback_sb_inodes

write to 0xffffc9000456fde8 of 8 bytes by task 9136 on cpu 1:
 wb_wait_for_completion_cb fs/fs-writeback.c:203 [inline]
 wb_wait_for_completion+0x1b9/0x360 fs/fs-writeback.c:226
 sync_inodes_sb+0x120/0x460 fs/fs-writeback.c:2894
 sync_inodes_one_sb+0x3d/0x50 fs/sync.c:77
 __iterate_supers+0x110/0x220 fs/super.c:924
 iterate_supers+0x1f/0x30 fs/super.c:939
 ksys_sync+0x5c/0xe0 fs/sync.c:102
 __ia32_sys_sync+0xe/0x20 fs/sync.c:113
 x64_sys_call+0x29b2/0x3000 arch/x86/include/generated/asm/syscalls_64.h:163
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xca/0x2b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffc9000456fde8 of 8 bytes by task 2691 on cpu 0:
 writeback_sb_inodes+0x4ce/0xb20 fs/fs-writeback.c:2033
 wb_writeback+0x252/0x5c0 fs/fs-writeback.c:2216
 wb_do_writeback fs/fs-writeback.c:2363 [inline]
 wb_workfn+0x194/0x910 fs/fs-writeback.c:2403
 process_one_work kernel/workqueue.c:3257 [inline]
 process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3340
 worker_thread+0x582/0x770 kernel/workqueue.c:3421
 kthread+0x489/0x510 kernel/kthread.c:463
 ret_from_fork+0x149/0x290 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

value changed: 0x00000000ffffc881 -> 0x00000000ffffc882

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 2691 Comm: kworker/u8:13 Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: writeback wb_workfn (flush-8:0)
==================================================================