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

write to 0xffff888137fbe5c0 of 8 bytes by task 14222 on cpu 0:
 inode_update_timestamps fs/inode.c:1907 [inline]
 generic_update_time fs/inode.c:1929 [inline]
 inode_update_time fs/inode.c:1949 [inline]
 touch_atime+0x31f/0x4a0 fs/inode.c:2020
 file_accessed include/linux/fs.h:2320 [inline]
 shmem_file_read_iter+0x570/0x5b0 mm/shmem.c:2845
 do_iter_read+0x4ac/0x7c0 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:2630 [inline]
 process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703
 worker_thread+0x525/0x730 kernel/workqueue.c:2784
 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:304

read to 0xffff888137fbe5c0 of 8 bytes by task 14228 on cpu 1:
 timespec64_equal include/linux/time64.h:49 [inline]
 inode_update_timestamps fs/inode.c:1906 [inline]
 generic_update_time fs/inode.c:1929 [inline]
 inode_update_time fs/inode.c:1949 [inline]
 touch_atime+0x2d8/0x4a0 fs/inode.c:2020
 file_accessed include/linux/fs.h:2320 [inline]
 shmem_file_read_iter+0x570/0x5b0 mm/shmem.c:2845
 do_iter_read+0x4ac/0x7c0 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:2630 [inline]
 process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703
 worker_thread+0x525/0x730 kernel/workqueue.c:2784
 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:304

value changed: 0x000000003255b0ce -> 0x00000000371a64cc

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 14228 Comm: kworker/u4:31 Not tainted 6.5.0-syzkaller-11075-g92901222f83d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Workqueue: loop4 loop_workfn
==================================================================