==================================================================
BUG: KCSAN: data-race in wq_worker_tick / wq_worker_tick

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+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
 __tsan_unaligned_volatile_read4+0x0/0x190 kernel/kcsan/core.c:753
 arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
 raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
 num_online_cpus include/linux/cpumask.h:1196 [inline]
 memcg_vmstats_needs_flush mm/memcontrol.c:560 [inline]
 memcg_rstat_updated mm/memcontrol.c:582 [inline]
 mod_memcg_state+0x1db/0x2b0 mm/memcontrol.c:702
 uncharge_batch+0x75/0x190 mm/memcontrol.c:4812
 __mem_cgroup_uncharge_folios+0x86/0xb0 mm/memcontrol.c:4906
 mem_cgroup_uncharge_folios include/linux/memcontrol.h:682 [inline]
 folios_put_refs+0x26e/0x2d0 mm/swap.c:996
 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:2721 [inline]
 io_ring_ctx_free+0x1ed/0x3a0 io_uring/io_uring.c:2810
 io_ring_exit_work+0x529/0x560 io_uring/io_uring.c:3032
 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+0x486/0x510 kernel/kthread.c:463
 ret_from_fork+0xda/0x150 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 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
 arch_atomic64_read arch/x86/include/asm/atomic64_64.h:15 [inline]
 raw_atomic64_read include/linux/atomic/atomic-arch-fallback.h:2583 [inline]
 raw_atomic_long_read include/linux/atomic/atomic-long.h:38 [inline]
 atomic_long_read include/linux/atomic/atomic-instrumented.h:3189 [inline]
 find_watchpoint kernel/kcsan/core.c:131 [inline]
 check_access kernel/kcsan/core.c:737 [inline]
 __tsan_unaligned_write8+0x2c/0x190 kernel/kcsan/core.c:1025
 perf_fetch_caller_regs include/linux/perf_event.h:1589 [inline]
 ____bpf_get_stackid_raw_tp kernel/trace/bpf_trace.c:1808 [inline]
 bpf_get_stackid_raw_tp+0xd8/0x120 kernel/trace/bpf_trace.c:1799
 bpf_prog_e6fc920cfeff8120+0x2a/0x32
 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+0x107/0x1c0 kernel/trace/bpf_trace.c:2298
 __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:4866
 io_free_region+0xa3/0x160 io_uring/memmap.c:104
 io_rings_free io_uring/io_uring.c:2721 [inline]
 io_ring_ctx_free+0x1ed/0x3a0 io_uring/io_uring.c:2810
 io_ring_exit_work+0x529/0x560 io_uring/io_uring.c:3032
 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+0x486/0x510 kernel/kthread.c:463
 ret_from_fork+0xda/0x150 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x000000000003a980 -> 0x000000000003d090

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 3690 Comm: kworker/u8:56 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: iou_exit io_ring_exit_work
==================================================================