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BUG: KCSAN: data-race in inode_update_timestamps / inode_update_timestamps

write to 0xffff88813a399280 of 8 bytes by task 11589 on cpu 1:
 inode_set_atime_to_ts include/linux/fs.h:1537 [inline]
 inode_update_timestamps+0x4d1/0x560 fs/inode.c:1914
 generic_update_time fs/inode.c:1936 [inline]
 inode_update_time fs/inode.c:1956 [inline]
 touch_atime+0x15c/0x2d0 fs/inode.c:2028
 file_accessed include/linux/fs.h:2360 [inline]
 shmem_file_read_iter+0x4b3/0x550 mm/shmem.c:2875
 do_iter_read+0x4af/0x780 fs/read_write.c:795
 vfs_iter_read+0x56/0x70 fs/read_write.c:837
 lo_read_simple drivers/block/loop.c:290 [inline]
 do_req_filebacked drivers/block/loop.c:500 [inline]
 loop_handle_cmd drivers/block/loop.c:1915 [inline]
 loop_process_work+0x98c/0x12e0 drivers/block/loop.c:1950
 loop_rootcg_workfn+0x22/0x30 drivers/block/loop.c:1981
 process_one_work kernel/workqueue.c:2627 [inline]
 process_scheduled_works+0x5b8/0xa30 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 to 0xffff88813a399280 of 8 bytes by task 20861 on cpu 0:
 inode_get_atime include/linux/fs.h:1531 [inline]
 inode_update_timestamps+0x498/0x560 fs/inode.c:1911
 generic_update_time fs/inode.c:1936 [inline]
 inode_update_time fs/inode.c:1956 [inline]
 touch_atime+0x15c/0x2d0 fs/inode.c:2028
 file_accessed include/linux/fs.h:2360 [inline]
 shmem_file_read_iter+0x4b3/0x550 mm/shmem.c:2875
 do_iter_read+0x4af/0x780 fs/read_write.c:795
 vfs_iter_read+0x56/0x70 fs/read_write.c:837
 lo_read_simple drivers/block/loop.c:290 [inline]
 do_req_filebacked drivers/block/loop.c:500 [inline]
 loop_handle_cmd drivers/block/loop.c:1915 [inline]
 loop_process_work+0x98c/0x12e0 drivers/block/loop.c:1950
 loop_workfn+0x31/0x40 drivers/block/loop.c:1974
 process_one_work kernel/workqueue.c:2627 [inline]
 process_scheduled_works+0x5b8/0xa30 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: 0x00000000103a0123 -> 0x0000000010d297a3

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 20861 Comm: kworker/u4:2 Not tainted 6.7.0-rc8-syzkaller-00174-g95c8a35f1c01 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Workqueue: loop2 loop_workfn
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