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BUG: KCSAN: data-race in tick_nohz_stop_tick / tick_sched_timer

write to 0xffffffff83cbf0d0 of 4 bytes by interrupt on cpu 0:
 tick_sched_do_timer kernel/time/tick-sched.c:191 [inline]
 tick_sched_timer+0x1f5/0x210 kernel/time/tick-sched.c:1366
 __run_hrtimer+0x160/0x480 kernel/time/hrtimer.c:1537
 __hrtimer_run_queues kernel/time/hrtimer.c:1601 [inline]
 hrtimer_interrupt+0x380/0xaf0 kernel/time/hrtimer.c:1663
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1089 [inline]
 __sysvec_apic_timer_interrupt+0x6f/0x1c0 arch/x86/kernel/apic/apic.c:1106
 sysvec_apic_timer_interrupt+0x64/0x80 arch/x86/kernel/apic/apic.c:1100
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:647
 mod_delayed_work_on+0x96/0xd0 kernel/workqueue.c:1723
 kblockd_mod_delayed_work_on+0x31/0x40 block/blk-core.c:1649
 __blk_mq_delay_run_hw_queue+0x2d2/0x2f0 block/blk-mq.c:1584
 blk_mq_run_hw_queue+0x22c/0x250 block/blk-mq.c:1629
 blk_mq_sched_insert_request+0x127/0x280 block/blk-mq-sched.c:469
 blk_mq_submit_bio+0x524/0xe90 block/blk-mq.c:2262
 __submit_bio_noacct_mq block/blk-core.c:1014 [inline]
 submit_bio_noacct+0x6f2/0x7e0 block/blk-core.c:1047
 submit_bio+0x16d/0x2b0 block/blk-core.c:1090
 submit_bh_wbc+0x2f3/0x330 fs/buffer.c:3075
 submit_bh fs/buffer.c:3081 [inline]
 __sync_dirty_buffer+0x136/0x1e0 fs/buffer.c:3176
 sync_dirty_buffer+0x16/0x20 fs/buffer.c:3189
 ext4_write_inode+0x285/0x390 fs/ext4/inode.c:5236
 write_inode+0x8c/0x180 fs/fs-writeback.c:1320
 __writeback_single_inode+0x2a2/0x450 fs/fs-writeback.c:1525
 writeback_single_inode+0x177/0x590 fs/fs-writeback.c:1580
 sync_inode fs/fs-writeback.c:2624 [inline]
 sync_inode_metadata+0x57/0x80 fs/fs-writeback.c:2644
 ext4_fsync_nojournal fs/ext4/fsync.c:92 [inline]
 ext4_sync_file+0x359/0x670 fs/ext4/fsync.c:170
 vfs_fsync_range+0x107/0x120 fs/sync.c:200
 generic_write_sync include/linux/fs.h:2982 [inline]
 ext4_buffered_write_iter+0x39c/0x3f0 fs/ext4/file.c:277
 ext4_file_write_iter+0x2e7/0x11d0 fs/ext4/file.c:519
 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_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffffffff83cbf0d0 of 4 bytes by task 0 on cpu 1:
 tick_nohz_stop_tick+0x73/0x3e0 kernel/time/tick-sched.c:836
 __tick_nohz_idle_stop_tick kernel/time/tick-sched.c:1022 [inline]
 tick_nohz_idle_stop_tick+0x15d/0x310 kernel/time/tick-sched.c:1043
 cpuidle_idle_call kernel/sched/idle.c:235 [inline]
 do_idle+0x186/0x240 kernel/sched/idle.c:306
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:403
 secondary_startup_64_no_verify+0xb0/0xbb

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 0 Comm: swapper/1 Tainted: G        W         5.13.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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