================================================================== BUG: KCSAN: data-race in touch_atime / touch_atime write to 0xffff88814a470ca0 of 8 bytes by task 19655 on cpu 1: inode_set_atime_to_ts include/linux/fs.h:1541 [inline] inode_update_timestamps fs/inode.c:1876 [inline] generic_update_time fs/inode.c:1898 [inline] inode_update_time fs/inode.c:1918 [inline] touch_atime+0x1ed/0x340 fs/inode.c:1990 file_accessed include/linux/fs.h:2437 [inline] shmem_file_read_iter+0x4b3/0x550 mm/shmem.c:2873 do_iter_readv_writev+0x2b0/0x330 vfs_iter_read+0x172/0x390 fs/read_write.c:830 lo_read_simple drivers/block/loop.c:286 [inline] do_req_filebacked drivers/block/loop.c:496 [inline] loop_handle_cmd drivers/block/loop.c:1909 [inline] loop_process_work+0x7a1/0x10e0 drivers/block/loop.c:1944 loop_rootcg_workfn+0x22/0x30 drivers/block/loop.c:1975 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x5b8/0xa40 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 0xffff88814a470ca0 of 8 bytes by task 19649 on cpu 0: inode_get_atime include/linux/fs.h:1535 [inline] inode_update_timestamps fs/inode.c:1873 [inline] generic_update_time fs/inode.c:1898 [inline] inode_update_time fs/inode.c:1918 [inline] touch_atime+0x19a/0x340 fs/inode.c:1990 file_accessed include/linux/fs.h:2437 [inline] shmem_file_read_iter+0x4b3/0x550 mm/shmem.c:2873 do_iter_readv_writev+0x2b0/0x330 vfs_iter_read+0x172/0x390 fs/read_write.c:830 lo_read_simple drivers/block/loop.c:286 [inline] do_req_filebacked drivers/block/loop.c:496 [inline] loop_handle_cmd drivers/block/loop.c:1909 [inline] loop_process_work+0x7a1/0x10e0 drivers/block/loop.c:1944 loop_workfn+0x31/0x40 drivers/block/loop.c:1968 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x5b8/0xa40 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: 0x000000000c25fd3b -> 0x000000000cbe93bb Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 19649 Comm: kworker/u4:57 Not tainted 6.8.0-rc2-syzkaller-00055-g6764c317b6bb #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Workqueue: loop2 loop_workfn ==================================================================