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BUG: KCSAN: data-race in expire_timers / try_to_del_timer_sync

write to 0xffff888237d376c8 of 8 bytes by interrupt on cpu 1:
 expire_timers+0x13d/0x250 kernel/time/timer.c:1463
 __run_timers+0x358/0x420 kernel/time/timer.c:1731
 run_timer_softirq+0x19/0x30 kernel/time/timer.c:1744
 __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
 _raw_spin_unlock_irqrestore+0x34/0x40 kernel/locking/spinlock.c:192
 spin_unlock_irqrestore include/linux/spinlock.h:409 [inline]
 unlock_page_lruvec_irqrestore include/linux/memcontrol.h:1497 [inline]
 pagevec_lru_move_fn+0x278/0x2d0 mm/swap.c:224
 activate_page mm/swap.c:360 [inline]
 mark_page_accessed+0x485/0x550 mm/swap.c:444
 shmem_getpage_gfp+0x2b4/0x13d0 mm/shmem.c:1858
 shmem_getpage mm/shmem.c:155 [inline]
 shmem_write_begin+0x7e/0x100 mm/shmem.c:2494
 generic_perform_write+0x196/0x3c0 mm/filemap.c:3656
 __generic_file_write_iter+0x161/0x300 mm/filemap.c:3783
 generic_file_write_iter+0x75/0x130 mm/filemap.c:3815
 call_write_iter include/linux/fs.h:2114 [inline]
 do_iter_readv_writev+0x2cb/0x360 fs/read_write.c:740
 do_iter_write+0x112/0x4c0 fs/read_write.c:866
 vfs_iter_write+0x4c/0x70 fs/read_write.c:907
 iter_file_splice_write+0x40a/0x750 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x650 fs/splice.c:891
 do_splice_direct+0xf5/0x170 fs/splice.c:979
 do_sendfile+0x773/0xda0 fs/read_write.c:1260
 __do_sys_sendfile64 fs/read_write.c:1325 [inline]
 __se_sys_sendfile64 fs/read_write.c:1311 [inline]
 __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1311
 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 0xffff888237d376c8 of 8 bytes by task 1779 on cpu 0:
 try_to_del_timer_sync+0xe3/0x290 kernel/time/timer.c:1231
 del_timer_sync kernel/time/timer.c:1378 [inline]
 schedule_timeout+0x108/0x240 kernel/time/timer.c:1879
 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: 0xffffc900004c7c50 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 1779 Comm: kworker/u4:6 Tainted: G        W         5.14.0-rc2-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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