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BUG: KCSAN: data-race in expire_timers / try_to_del_timer_sync

write to 0xffff888237c376c8 of 8 bytes by interrupt on cpu 0:
 expire_timers+0x13d/0x250 kernel/time/timer.c:1465
 __run_timers+0x358/0x420 kernel/time/timer.c:1732
 run_timer_softirq+0x19/0x30 kernel/time/timer.c:1745
 __do_softirq+0x12c/0x26e kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x9a/0xb0 kernel/softirq.c:636
 sysvec_apic_timer_interrupt+0x69/0x80 arch/x86/kernel/apic/apic.c:1100
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
 invalidate_bh_lrus_cpu+0xd0/0xe0 fs/buffer.c:1436
 lru_add_drain_cpu+0x243/0x270 mm/swap.c:645
 lru_add_drain+0x28/0x40 mm/swap.c:724
 follow_page_pte mm/gup.c:604 [inline]
 follow_pmd_mask mm/gup.c:682 [inline]
 follow_pud_mask mm/gup.c:765 [inline]
 follow_p4d_mask mm/gup.c:791 [inline]
 follow_page_mask+0xdc8/0x1040 mm/gup.c:850
 __get_user_pages+0x2e6/0xbc0 mm/gup.c:1171
 populate_vma_page_range mm/gup.c:1506 [inline]
 __mm_populate+0x24d/0x380 mm/gup.c:1612
 mm_populate include/linux/mm.h:2623 [inline]
 __do_sys_mlockall+0x246/0x2c0 mm/mlock.c:799
 __se_sys_mlockall mm/mlock.c:775 [inline]
 __x64_sys_mlockall+0x1a/0x20 mm/mlock.c:775
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888237c376c8 of 8 bytes by task 22 on cpu 1:
 try_to_del_timer_sync+0xe3/0x290 kernel/time/timer.c:1233
 del_timer_sync kernel/time/timer.c:1380 [inline]
 schedule_timeout+0x108/0x240 kernel/time/timer.c:1880
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common+0xc6/0x150 kernel/sched/completion.c:117
 io_ring_exit_work+0x221/0x1350 fs/io_uring.c:8803
 process_one_work+0x3e9/0x8f0 kernel/workqueue.c:2276
 worker_thread+0x636/0xae0 kernel/workqueue.c:2422
 kthread+0x262/0x280 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

value changed: 0xffffc900002dbc50 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 22 Comm: kworker/u4:1 Tainted: G        W         5.14.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_unbound io_ring_exit_work
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