================================================================== BUG: KCSAN: data-race in wq_worker_tick / wq_worker_tick read-write to 0xffff88810006ceb8 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:5622 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:1038 [inline] __sysvec_apic_timer_interrupt+0x5c/0x1d0 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x6e/0x80 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 is_atomic kernel/kcsan/core.c:249 [inline] should_watch kernel/kcsan/core.c:277 [inline] check_access kernel/kcsan/core.c:752 [inline] __tsan_unaligned_write4+0x12a/0x180 kernel/kcsan/core.c:1024 skb_set_end_offset include/linux/skbuff.h:1679 [inline] __finalize_skb_around net/core/skbuff.c:383 [inline] __build_skb_around+0xf8/0x1f0 net/core/skbuff.c:448 __alloc_skb+0x1e9/0x310 net/core/skbuff.c:693 alloc_skb include/linux/skbuff.h:1322 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline] nsim_dev_trap_report_work+0x18d/0x5b0 drivers/net/netdevsim/dev.c:851 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 0xffff88810006ceb8 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:5622 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:1038 [inline] __sysvec_apic_timer_interrupt+0x5c/0x1d0 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x6e/0x80 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 crng_make_state+0x1c6/0x3e0 _get_random_bytes+0x88/0x190 drivers/char/random.c:406 get_random_bytes+0x1d/0x30 drivers/char/random.c:438 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:775 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline] nsim_dev_trap_report_work+0x414/0x5b0 drivers/net/netdevsim/dev.c:851 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: 0x00000000004fa6a0 -> 0x00000000004fcdb0 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 3969 Comm: kworker/u8:10 Not tainted 6.12.0-rc6-syzkaller-00318-ga9cda7c0ffed #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_unbound nsim_dev_trap_report_work ==================================================================