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BUG: KCSAN: data-race in wq_worker_tick / wq_worker_tick

read-write to 0xffff88810107c0b8 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: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: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
 arch_try_cmpxchg128 arch/x86/include/asm/cmpxchg_64.h:83 [inline]
 __update_freelist_fast mm/slub.c:766 [inline]
 slab_update_freelist+0x6c/0x100 mm/slub.c:836
 __slab_free+0x77/0x270 mm/slub.c:5911
 do_slab_free mm/slub.c:6582 [inline]
 slab_free mm/slub.c:6651 [inline]
 kfree+0x2d3/0x400 mm/slub.c:6849
 io_alloc_cache_free+0xc0/0xe0 io_uring/alloc_cache.c:16
 io_free_alloc_caches+0x2f/0x70 io_uring/io_uring.c:310
 io_ring_ctx_free+0x78/0x3a0 io_uring/io_uring.c:2849
 io_ring_exit_work+0x529/0x560 io_uring/io_uring.c:3086
 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 0xffff88810107c0b8 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: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: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
 page_counter_uncharge+0x2e/0x60 mm/page_counter.c:183
 memcg1_account_kmem+0x32/0x40 mm/memcontrol-v1.c:2171
 uncharge_batch+0x95/0x190 mm/memcontrol.c:4812
 __mem_cgroup_uncharge_folios+0x86/0xb0 mm/memcontrol.c:4905
 mem_cgroup_uncharge_folios include/linux/memcontrol.h:690 [inline]
 folios_put_refs+0x26e/0x2d0 mm/swap.c:1001
 release_pages+0x2a8/0x2f0 mm/swap.c:1042
 io_free_region+0x7b/0x160 io_uring/memmap.c:102
 io_rings_free io_uring/io_uring.c:2770 [inline]
 io_ring_ctx_free+0x1ed/0x3a0 io_uring/io_uring.c:2864
 io_ring_exit_work+0x529/0x560 io_uring/io_uring.c:3086
 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: 0x000000000013af10 -> 0x000000000013d620

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 9701 Comm: kworker/u8:44 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
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