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BUG: KCSAN: data-race in touch_atime / touch_atime

write to 0xffff88811a13e3d0 of 4 bytes by task 1298 on cpu 1:
 inode_set_atime_to_ts include/linux/fs.h:1672 [inline]
 inode_update_timestamps fs/inode.c:2035 [inline]
 generic_update_time fs/inode.c:2057 [inline]
 inode_update_time fs/inode.c:2077 [inline]
 touch_atime+0x1f3/0x350 fs/inode.c:2149
 file_accessed include/linux/fs.h:2599 [inline]
 shmem_file_read_iter+0x474/0x540 mm/shmem.c:3457
 do_iter_readv_writev+0x40d/0x4b0 fs/read_write.c:-1
 vfs_iter_read+0x171/0x3b0 fs/read_write.c:914
 lo_read_simple drivers/block/loop.c:261 [inline]
 do_req_filebacked drivers/block/loop.c:501 [inline]
 loop_handle_cmd drivers/block/loop.c:1943 [inline]
 loop_process_work+0x7c2/0x1240 drivers/block/loop.c:1978
 loop_workfn+0x31/0x40 drivers/block/loop.c:2002
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x4de/0xa20 kernel/workqueue.c:3319
 worker_thread+0x52c/0x710 kernel/workqueue.c:3400
 kthread+0x4b7/0x540 kernel/kthread.c:464
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff88811a13e3d0 of 4 bytes by task 3411 on cpu 0:
 inode_get_atime_nsec include/linux/fs.h:1657 [inline]
 inode_get_atime include/linux/fs.h:1663 [inline]
 inode_update_timestamps fs/inode.c:2032 [inline]
 generic_update_time fs/inode.c:2057 [inline]
 inode_update_time fs/inode.c:2077 [inline]
 touch_atime+0x1a0/0x350 fs/inode.c:2149
 file_accessed include/linux/fs.h:2599 [inline]
 shmem_file_read_iter+0x474/0x540 mm/shmem.c:3457
 do_iter_readv_writev+0x40d/0x4b0 fs/read_write.c:-1
 vfs_iter_read+0x171/0x3b0 fs/read_write.c:914
 lo_read_simple drivers/block/loop.c:261 [inline]
 do_req_filebacked drivers/block/loop.c:501 [inline]
 loop_handle_cmd drivers/block/loop.c:1943 [inline]
 loop_process_work+0x7c2/0x1240 drivers/block/loop.c:1978
 loop_rootcg_workfn+0x22/0x30 drivers/block/loop.c:2009
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x4de/0xa20 kernel/workqueue.c:3319
 worker_thread+0x52c/0x710 kernel/workqueue.c:3400
 kthread+0x4b7/0x540 kernel/kthread.c:464
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x2437ce59 -> 0x24d064d9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3411 Comm: kworker/u8:7 Not tainted 6.14.0-syzkaller-10892-g4e82c87058f4 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: loop4 loop_rootcg_workfn
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