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BUG: KCSAN: data-race in wq_worker_tick / wq_worker_tick

read-write to 0xffff888101217cb8 of 8 bytes by interrupt on cpu 1:
 wq_worker_tick+0x60/0x230 kernel/workqueue.c:1474
 sched_tick+0xd7/0x220 kernel/sched/core.c:5546
 update_process_times+0x15f/0x190 kernel/time/timer.c:2479
 tick_sched_handle kernel/time/tick-sched.c:298 [inline]
 tick_nohz_handler+0x276/0x3d0 kernel/time/tick-sched.c:319
 __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:1045 [inline]
 __sysvec_apic_timer_interrupt+0x5f/0x1d0 arch/x86/kernel/apic/apic.c:1062
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x6f/0x80 arch/x86/kernel/apic/apic.c:1056
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
 kcsan_setup_watchpoint+0x415/0x430 kernel/kcsan/core.c:705
 __account_obj_stock+0x2c/0x350 mm/memcontrol.c:2873
 refill_obj_stock+0x202/0x2e0 mm/memcontrol.c:3043
 __memcg_slab_free_hook+0x1b3/0x230 mm/memcontrol.c:3207
 memcg_slab_free_hook mm/slub.c:2364 [inline]
 slab_free mm/slub.c:6660 [inline]
 kfree+0x2b9/0x3c0 mm/slub.c:6871
 io_remove_buffers_legacy io_uring/kbuf.c:422 [inline]
 io_put_bl+0xfe/0x160 io_uring/kbuf.c:433
 io_destroy_buffers+0xc7/0x170 io_uring/kbuf.c:452
 io_ring_ctx_free+0x82/0x3d0 io_uring/io_uring.c:2849
 io_ring_exit_work+0x4ef/0x520 io_uring/io_uring.c:3073
 process_one_work kernel/workqueue.c:3257 [inline]
 process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3340
 worker_thread+0x582/0x770 kernel/workqueue.c:3421
 kthread+0x489/0x510 kernel/kthread.c:463
 ret_from_fork+0x149/0x290 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

read-write to 0xffff888101217cb8 of 8 bytes by interrupt on cpu 0:
 wq_worker_tick+0x60/0x230 kernel/workqueue.c:1474
 sched_tick+0xd7/0x220 kernel/sched/core.c:5546
 update_process_times+0x15f/0x190 kernel/time/timer.c:2479
 tick_sched_handle kernel/time/tick-sched.c:298 [inline]
 tick_nohz_handler+0x276/0x3d0 kernel/time/tick-sched.c:319
 __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:1045 [inline]
 __sysvec_apic_timer_interrupt+0x5f/0x1d0 arch/x86/kernel/apic/apic.c:1062
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x6f/0x80 arch/x86/kernel/apic/apic.c:1056
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
 preempt_count arch/x86/include/asm/preempt.h:27 [inline]
 get_ctx kernel/kcsan/core.c:206 [inline]
 check_access kernel/kcsan/core.c:750 [inline]
 __tsan_read4+0xbe/0x190 kernel/kcsan/core.c:1024
 refill_obj_stock+0x211/0x2e0 mm/memcontrol.c:3045
 __memcg_slab_free_hook+0x1b3/0x230 mm/memcontrol.c:3207
 memcg_slab_free_hook mm/slub.c:2364 [inline]
 slab_free mm/slub.c:6660 [inline]
 kmem_cache_free+0x284/0x3a0 mm/slub.c:6774
 __io_req_caches_free+0xfe/0x210 io_uring/io_uring.c:2823
 io_req_caches_free+0x1f/0x60 io_uring/io_uring.c:2835
 io_ring_exit_work+0x23b/0x520 io_uring/io_uring.c:3021
 process_one_work kernel/workqueue.c:3257 [inline]
 process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3340
 worker_thread+0x582/0x770 kernel/workqueue.c:3421
 kthread+0x489/0x510 kernel/kthread.c:463
 ret_from_fork+0x149/0x290 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

value changed: 0x00000000000f1b30 -> 0x00000000000f4240

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 52 Comm: kworker/u8:3 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: iou_exit io_ring_exit_work
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