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BUG: KCSAN: data-race in file_update_time / inode_update_timestamps

write to 0xffff888107e28ee8 of 4 bytes by task 35 on cpu 1:
 inode_set_ctime_to_ts include/linux/fs.h:1637 [inline]
 inode_set_ctime_current fs/inode.c:2591 [inline]
 inode_update_timestamps+0xaf/0x280 fs/inode.c:1923
 generic_update_time fs/inode.c:1962 [inline]
 inode_update_time fs/inode.c:1982 [inline]
 __file_update_time fs/inode.c:2171 [inline]
 file_update_time+0x229/0x2c0 fs/inode.c:2201
 pipe_write+0xa87/0xd30 fs/pipe.c:607
 __kernel_write_iter+0x24f/0x4e0 fs/read_write.c:523
 __kernel_write fs/read_write.c:543 [inline]
 kernel_write+0x1f3/0x410 fs/read_write.c:564
 p9_fd_write net/9p/trans_fd.c:432 [inline]
 p9_write_work+0x32a/0x750 net/9p/trans_fd.c:483
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3312
 worker_thread+0x526/0x700 kernel/workqueue.c:3390
 kthread+0x1d1/0x210 kernel/kthread.c:389
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

read to 0xffff888107e28ee8 of 4 bytes by task 8 on cpu 0:
 inode_get_ctime_nsec include/linux/fs.h:1622 [inline]
 inode_get_ctime include/linux/fs.h:1628 [inline]
 inode_needs_update_time fs/inode.c:2154 [inline]
 file_update_time+0x104/0x2c0 fs/inode.c:2197
 pipe_write+0xa87/0xd30 fs/pipe.c:607
 __kernel_write_iter+0x24f/0x4e0 fs/read_write.c:523
 __kernel_write fs/read_write.c:543 [inline]
 kernel_write+0x1f3/0x410 fs/read_write.c:564
 p9_fd_write net/9p/trans_fd.c:432 [inline]
 p9_write_work+0x32a/0x750 net/9p/trans_fd.c:483
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3312
 worker_thread+0x526/0x700 kernel/workqueue.c:3390
 kthread+0x1d1/0x210 kernel/kthread.c:389
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

value changed: 0x0de9f280 -> 0x0e8accb8

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 8 Comm: kworker/0:0 Not tainted 6.11.0-rc2-syzkaller-00042-gcf6d429eb656 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Workqueue: events p9_write_work
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