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BUG: KCSAN: data-race in wq_worker_tick / wq_worker_tick

read-write to 0xffff8881012056b8 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+0x20c/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
 __preempt_count_dec_and_test arch/x86/include/asm/preempt.h:95 [inline]
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0x3c/0x60 kernel/locking/spinlock.c:194
 free_frozen_page_commit+0x1f9/0x2a0 mm/page_alloc.c:2869
 __free_frozen_pages+0x252/0x4e0 mm/page_alloc.c:2923
 discard_slab mm/slub.c:2753 [inline]
 __put_partials+0x128/0x150 mm/slub.c:3218
 put_cpu_partial+0x8d/0xb0 mm/slub.c:3293
 do_slab_free mm/slub.c:4632 [inline]
 slab_free mm/slub.c:4681 [inline]
 kfree+0x193/0x320 mm/slub.c:4879
 io_alloc_cache_free+0xc0/0xe0 io_uring/alloc_cache.c:16
 io_free_alloc_caches+0x2f/0x80 io_uring/io_uring.c:290
 io_ring_ctx_free+0x78/0x3a0 io_uring/io_uring.c:2794
 io_ring_exit_work+0x529/0x560 io_uring/io_uring.c:3031
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3319
 worker_thread+0x582/0x770 kernel/workqueue.c:3400
 kthread+0x489/0x510 kernel/kthread.c:464
 ret_from_fork+0xdd/0x150 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read-write to 0xffff8881012056b8 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+0x20c/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
 __preempt_count_dec_and_test arch/x86/include/asm/preempt.h:95 [inline]
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0x3c/0x60 kernel/locking/spinlock.c:194
 free_frozen_page_commit+0x1f9/0x2a0 mm/page_alloc.c:2869
 free_unref_folios+0x69d/0x750 mm/page_alloc.c:3023
 folios_put_refs+0x276/0x2d0 mm/swap.c:997
 release_pages+0x2a8/0x2f0 mm/swap.c:1037
 io_free_region+0x7b/0x160 io_uring/memmap.c:102
 io_rings_free io_uring/io_uring.c:2720 [inline]
 io_ring_ctx_free+0x1ed/0x3a0 io_uring/io_uring.c:2809
 io_ring_exit_work+0x529/0x560 io_uring/io_uring.c:3031
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3319
 worker_thread+0x582/0x770 kernel/workqueue.c:3400
 kthread+0x489/0x510 kernel/kthread.c:464
 ret_from_fork+0xdd/0x150 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x00000000000a8750 -> 0x00000000000aae60

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 8042 Comm: kworker/u8:35 Not tainted 6.16.0-syzkaller-11241-g186f3edfdd41 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: iou_exit io_ring_exit_work
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