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BUG: KCSAN: data-race in wq_worker_tick / wq_worker_tick

read-write to 0xffff8881012426b8 of 8 bytes by interrupt on cpu 1:
 wq_worker_tick+0x60/0x230 kernel/workqueue.c:1478
 sched_tick+0x11a/0x270 kernel/sched/core.c:5648
 update_process_times+0x15f/0x190 kernel/time/timer.c:2478
 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:1761 [inline]
 __hrtimer_run_queues+0x20f/0x5a0 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x21a/0x460 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
 __sysvec_apic_timer_interrupt+0x5c/0x1d0 arch/x86/kernel/apic/apic.c:1056
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0x6f/0x80 arch/x86/kernel/apic/apic.c:1050
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
 orc_find arch/x86/kernel/unwind_orc.c:217 [inline]
 unwind_next_frame+0xa7/0xc80 arch/x86/kernel/unwind_orc.c:494
 perf_callchain_kernel+0x2d7/0x330 arch/x86/events/core.c:2798
 get_perf_callchain+0x424/0x530 kernel/events/callchain.c:240
 __bpf_get_stack+0x260/0x630 kernel/bpf/stackmap.c:454
 ____bpf_get_stack kernel/bpf/stackmap.c:499 [inline]
 bpf_get_stack+0x33/0x50 kernel/bpf/stackmap.c:496
 ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1835 [inline]
 bpf_get_stack_raw_tp+0x106/0x130 kernel/trace/bpf_trace.c:1825
 bpf_prog_d43750871481577d+0x46/0x4e
 bpf_dispatcher_nop_func include/linux/bpf.h:1332 [inline]
 __bpf_prog_run include/linux/filter.h:718 [inline]
 bpf_prog_run include/linux/filter.h:725 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2257 [inline]
 bpf_trace_run2+0x104/0x1c0 kernel/trace/bpf_trace.c:2298
 __traceiter_kfree+0x2e/0x50 include/trace/events/kmem.h:94
 __do_trace_kfree include/trace/events/kmem.h:94 [inline]
 trace_kfree include/trace/events/kmem.h:94 [inline]
 kfree+0x27b/0x320 mm/slub.c:4881
 io_free_region+0xa3/0x160 io_uring/memmap.c:104
 io_rings_free io_uring/io_uring.c:2718 [inline]
 io_ring_ctx_free+0x1de/0x3a0 io_uring/io_uring.c:2808
 io_ring_exit_work+0x529/0x560 io_uring/io_uring.c:3030
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0x4cb/0x9d0 kernel/workqueue.c:3319
 worker_thread+0x582/0x770 kernel/workqueue.c:3400
 kthread+0x489/0x510 kernel/kthread.c:463
 ret_from_fork+0x11f/0x1b0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read-write to 0xffff8881012426b8 of 8 bytes by interrupt on cpu 0:
 wq_worker_tick+0x60/0x230 kernel/workqueue.c:1478
 sched_tick+0x11a/0x270 kernel/sched/core.c:5648
 update_process_times+0x15f/0x190 kernel/time/timer.c:2478
 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:1761 [inline]
 __hrtimer_run_queues+0x20f/0x5a0 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x21a/0x460 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
 __sysvec_apic_timer_interrupt+0x5c/0x1d0 arch/x86/kernel/apic/apic.c:1056
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0x6f/0x80 arch/x86/kernel/apic/apic.c:1050
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
 strncpy_from_kernel_nofault+0x112/0x130 mm/maccess.c:90
 bpf_probe_read_kernel_str_common kernel/trace/bpf_trace.c:265 [inline]
 ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:313 [inline]
 bpf_probe_read_compat_str+0xdb/0x130 kernel/trace/bpf_trace.c:306
 bpf_prog_200610361a7cb5a8+0x43/0x49
 bpf_dispatcher_nop_func include/linux/bpf.h:1332 [inline]
 __bpf_prog_run include/linux/filter.h:718 [inline]
 bpf_prog_run include/linux/filter.h:725 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2257 [inline]
 bpf_trace_run2+0x104/0x1c0 kernel/trace/bpf_trace.c:2298
 __traceiter_kfree+0x2e/0x50 include/trace/events/kmem.h:94
 __do_trace_kfree include/trace/events/kmem.h:94 [inline]
 trace_kfree include/trace/events/kmem.h:94 [inline]
 kfree+0x27b/0x320 mm/slub.c:4881
 io_ring_ctx_free+0x313/0x3a0 io_uring/io_uring.c:2822
 io_ring_exit_work+0x529/0x560 io_uring/io_uring.c:3030
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0x4cb/0x9d0 kernel/workqueue.c:3319
 worker_thread+0x582/0x770 kernel/workqueue.c:3400
 kthread+0x489/0x510 kernel/kthread.c:463
 ret_from_fork+0x11f/0x1b0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x0000000000cdfe60 -> 0x0000000000ce2570

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 4223 Comm: kworker/u8:8 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: iou_exit io_ring_exit_work
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