================================================================== BUG: KCSAN: data-race in wq_worker_tick / wq_worker_tick read-write to 0xffff888104409cb8 of 8 bytes by interrupt on cpu 0: wq_worker_tick+0x63/0x240 kernel/workqueue.c:1474 sched_tick+0xd2/0x110 kernel/sched/core.c:5609 update_process_times+0x15a/0x180 kernel/time/timer.c:2524 tick_sched_handle kernel/time/tick-sched.c:276 [inline] tick_nohz_handler+0x250/0x2d0 kernel/time/tick-sched.c:297 __run_hrtimer kernel/time/hrtimer.c:1691 [inline] __hrtimer_run_queues+0x20d/0x5e0 kernel/time/hrtimer.c:1755 hrtimer_interrupt+0x210/0x7b0 kernel/time/hrtimer.c:1817 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1026 [inline] __sysvec_apic_timer_interrupt+0x5c/0x1a0 arch/x86/kernel/apic/apic.c:1043 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline] sysvec_apic_timer_interrupt+0x6e/0x80 arch/x86/kernel/apic/apic.c:1037 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 iov_iter_count include/linux/uio.h:307 [inline] generic_perform_write+0xa2/0x4a0 mm/filemap.c:4032 shmem_file_write_iter+0xc2/0xe0 mm/shmem.c:3221 do_iter_readv_writev+0x394/0x450 vfs_iter_write+0x265/0x5d0 fs/read_write.c:988 lo_write_bvec drivers/block/loop.c:243 [inline] lo_write_simple drivers/block/loop.c:264 [inline] do_req_filebacked drivers/block/loop.c:511 [inline] loop_handle_cmd drivers/block/loop.c:1910 [inline] loop_process_work+0xac7/0x1220 drivers/block/loop.c:1945 loop_workfn+0x31/0x40 drivers/block/loop.c:1969 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3310 worker_thread+0x51d/0x6f0 kernel/workqueue.c:3391 kthread+0x1d1/0x210 kernel/kthread.c:389 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 read-write to 0xffff888104409cb8 of 8 bytes by interrupt on cpu 1: wq_worker_tick+0x63/0x240 kernel/workqueue.c:1474 sched_tick+0xd2/0x110 kernel/sched/core.c:5609 update_process_times+0x15a/0x180 kernel/time/timer.c:2524 tick_sched_handle kernel/time/tick-sched.c:276 [inline] tick_nohz_handler+0x250/0x2d0 kernel/time/tick-sched.c:297 __run_hrtimer kernel/time/hrtimer.c:1691 [inline] __hrtimer_run_queues+0x20d/0x5e0 kernel/time/hrtimer.c:1755 hrtimer_interrupt+0x210/0x7b0 kernel/time/hrtimer.c:1817 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1026 [inline] __sysvec_apic_timer_interrupt+0x5c/0x1a0 arch/x86/kernel/apic/apic.c:1043 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline] sysvec_apic_timer_interrupt+0x6e/0x80 arch/x86/kernel/apic/apic.c:1037 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 selinux_cred security/selinux/include/objsec.h:154 [inline] current_sid security/selinux/include/objsec.h:187 [inline] selinux_file_permission+0x96/0x360 security/selinux/hooks.c:3629 security_file_permission+0x3d/0x80 security/security.c:2839 rw_verify_area fs/read_write.c:470 [inline] vfs_iter_write+0x151/0x5d0 fs/read_write.c:983 lo_write_bvec drivers/block/loop.c:243 [inline] lo_write_simple drivers/block/loop.c:264 [inline] do_req_filebacked drivers/block/loop.c:511 [inline] loop_handle_cmd drivers/block/loop.c:1910 [inline] loop_process_work+0xac7/0x1220 drivers/block/loop.c:1945 loop_rootcg_workfn+0x22/0x30 drivers/block/loop.c:1976 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3310 worker_thread+0x51d/0x6f0 kernel/workqueue.c:3391 kthread+0x1d1/0x210 kernel/kthread.c:389 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 value changed: 0x0000000000011170 -> 0x0000000000013880 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 330 Comm: kworker/u8:5 Tainted: G W 6.11.0-syzkaller-11728-gad46e8f95e93 #0 Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: loop4 loop_rootcg_workfn ==================================================================