================================================================== BUG: KCSAN: data-race in wq_worker_tick / wq_worker_tick read-write to 0xffff88810123c8b8 of 8 bytes by interrupt on cpu 0: wq_worker_tick+0x60/0x230 kernel/workqueue.c:1480 sched_tick+0x11a/0x270 kernel/sched/core.c:5616 update_process_times+0x15f/0x190 kernel/time/timer.c:2479 tick_sched_handle kernel/time/tick-sched.c:276 [inline] tick_nohz_handler+0x249/0x2d0 kernel/time/tick-sched.c:297 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x20f/0x5a0 kernel/time/hrtimer.c:1841 hrtimer_interrupt+0x21a/0x460 kernel/time/hrtimer.c:1903 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline] __sysvec_apic_timer_interrupt+0x5f/0x1d0 arch/x86/kernel/apic/apic.c:1058 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0x6f/0x80 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 kcsan_setup_watchpoint+0x415/0x430 kernel/kcsan/core.c:705 __bpf_prog_run include/linux/filter.h:721 [inline] bpf_prog_run include/linux/filter.h:728 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2075 [inline] bpf_trace_run3+0xfd/0x1d0 kernel/trace/bpf_trace.c:2117 __traceiter_kmem_cache_free+0x38/0x60 include/trace/events/kmem.h:117 __do_trace_kmem_cache_free include/trace/events/kmem.h:117 [inline] trace_kmem_cache_free include/trace/events/kmem.h:117 [inline] kmem_cache_free+0x329/0x3d0 mm/slub.c:6751 __io_req_caches_free+0xfe/0x210 io_uring/io_uring.c:2824 io_req_caches_free+0x1f/0x60 io_uring/io_uring.c:2836 io_ring_exit_work+0x26d/0x560 io_uring/io_uring.c:3034 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3346 worker_thread+0x582/0x770 kernel/workqueue.c:3427 kthread+0x489/0x510 kernel/kthread.c:463 ret_from_fork+0x122/0x1b0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 read-write to 0xffff88810123c8b8 of 8 bytes by interrupt on cpu 1: wq_worker_tick+0x60/0x230 kernel/workqueue.c:1480 sched_tick+0x11a/0x270 kernel/sched/core.c:5616 update_process_times+0x15f/0x190 kernel/time/timer.c:2479 tick_sched_handle kernel/time/tick-sched.c:276 [inline] tick_nohz_handler+0x249/0x2d0 kernel/time/tick-sched.c:297 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x20f/0x5a0 kernel/time/hrtimer.c:1841 hrtimer_interrupt+0x21a/0x460 kernel/time/hrtimer.c:1903 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline] __sysvec_apic_timer_interrupt+0x5f/0x1d0 arch/x86/kernel/apic/apic.c:1058 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0x6f/0x80 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 get_current arch/x86/include/asm/current.h:25 [inline] __sanitizer_cov_trace_pc+0x11/0x70 kernel/kcov.c:216 strncpy_from_user_nofault+0x1c/0xf0 mm/maccess.c:185 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:214 [inline] ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:223 [inline] bpf_probe_read_user_str+0x2a/0x70 kernel/trace/bpf_trace.c:220 bpf_prog_640d0361f19ec9d4+0x40/0x46 bpf_dispatcher_nop_func include/linux/bpf.h:1350 [inline] __bpf_prog_run include/linux/filter.h:721 [inline] bpf_prog_run include/linux/filter.h:728 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2075 [inline] bpf_trace_run3+0x10f/0x1d0 kernel/trace/bpf_trace.c:2117 __traceiter_kmem_cache_free+0x38/0x60 include/trace/events/kmem.h:117 __do_trace_kmem_cache_free include/trace/events/kmem.h:117 [inline] trace_kmem_cache_free include/trace/events/kmem.h:117 [inline] kmem_cache_free+0x329/0x3d0 mm/slub.c:6751 __io_req_caches_free+0xfe/0x210 io_uring/io_uring.c:2824 io_req_caches_free+0x1f/0x60 io_uring/io_uring.c:2836 io_ring_exit_work+0x26d/0x560 io_uring/io_uring.c:3034 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3346 worker_thread+0x582/0x770 kernel/workqueue.c:3427 kthread+0x489/0x510 kernel/kthread.c:463 ret_from_fork+0x122/0x1b0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 value changed: 0x0000000000264cb0 -> 0x00000000002673c0 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 31 Comm: kworker/u8:1 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: iou_exit io_ring_exit_work ==================================================================