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BUG: KCSAN: data-race in inode_update_timestamps / inode_update_timestamps

write to 0xffff8881031c78b0 of 8 bytes by task 38 on cpu 0:
 inode_set_atime_to_ts include/linux/fs.h:1541 [inline]
 inode_update_timestamps+0x4d1/0x560 fs/inode.c:1876
 generic_update_time fs/inode.c:1898 [inline]
 inode_update_time fs/inode.c:1918 [inline]
 touch_atime+0x15c/0x2d0 fs/inode.c:1990
 file_accessed include/linux/fs.h:2437 [inline]
 shmem_file_read_iter+0x4b3/0x550 mm/shmem.c:2873
 vfs_iter_read+0x2d8/0x560 fs/read_write.c:830
 lo_read_simple drivers/block/loop.c:288 [inline]
 do_req_filebacked drivers/block/loop.c:498 [inline]
 loop_handle_cmd drivers/block/loop.c:1911 [inline]
 loop_process_work+0x79f/0x10e0 drivers/block/loop.c:1946
 loop_rootcg_workfn+0x22/0x30 drivers/block/loop.c:1977
 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 0xffff8881031c78b0 of 8 bytes by task 3098 on cpu 1:
 inode_get_atime include/linux/fs.h:1535 [inline]
 inode_update_timestamps+0x498/0x560 fs/inode.c:1873
 generic_update_time fs/inode.c:1898 [inline]
 inode_update_time fs/inode.c:1918 [inline]
 touch_atime+0x15c/0x2d0 fs/inode.c:1990
 file_accessed include/linux/fs.h:2437 [inline]
 shmem_file_read_iter+0x4b3/0x550 mm/shmem.c:2873
 vfs_iter_read+0x2d8/0x560 fs/read_write.c:830
 lo_read_simple drivers/block/loop.c:288 [inline]
 do_req_filebacked drivers/block/loop.c:498 [inline]
 loop_handle_cmd drivers/block/loop.c:1911 [inline]
 loop_process_work+0x79f/0x10e0 drivers/block/loop.c:1946
 loop_workfn+0x31/0x40 drivers/block/loop.c:1970
 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

value changed: 0x0000000023cd6188 -> 0x000000002d56c98b

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 3098 Comm: kworker/u4:5 Not tainted 6.7.0-syzkaller-10085-g1b1934dbbdcf #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Workqueue: loop2 loop_workfn
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