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BUG: KCSAN: data-race in __blk_mq_sched_dispatch_requests / blk_mq_do_dispatch_sched

write to 0xffff888102effc10 of 8 bytes by task 2130 on cpu 0:
 INIT_LIST_HEAD include/linux/list.h:36 [inline]
 list_splice_init include/linux/list.h:483 [inline]
 __blk_mq_sched_dispatch_requests+0x16a/0x2a0 block/blk-mq-sched.c:289
 blk_mq_sched_dispatch_requests+0x9f/0x110 block/blk-mq-sched.c:341
 __blk_mq_run_hw_queue+0xc1/0x140 block/blk-mq.c:1488
 __blk_mq_delay_run_hw_queue+0x188/0x330 block/blk-mq.c:1565
 blk_mq_run_hw_queue+0x231/0x260 block/blk-mq.c:1618
 blk_mq_run_hw_queues+0x1d1/0x230 block/blk-mq.c:1681
 blk_mq_requeue_work+0x3bd/0x3f0 block/blk-mq.c:797
 process_one_work+0x3e1/0x950 kernel/workqueue.c:2275
 worker_thread+0x616/0xa70 kernel/workqueue.c:2421
 kthread+0x20b/0x230 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

read to 0xffff888102effc10 of 8 bytes by task 2012 on cpu 1:
 list_empty_careful include/linux/list.h:319 [inline]
 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:138 [inline]
 blk_mq_do_dispatch_sched+0x17c/0x610 block/blk-mq-sched.c:199
 __blk_mq_sched_dispatch_requests+0x1fd/0x2a0 block/blk-mq-sched.c:310
 blk_mq_sched_dispatch_requests+0x9f/0x110 block/blk-mq-sched.c:341
 __blk_mq_run_hw_queue+0xc1/0x140 block/blk-mq.c:1488
 blk_mq_run_work_fn+0x3d/0x50 block/blk-mq.c:1820
 process_one_work+0x3e1/0x950 kernel/workqueue.c:2275
 worker_thread+0x616/0xa70 kernel/workqueue.c:2421
 kthread+0x20b/0x230 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 2012 Comm: kworker/1:1H Not tainted 5.12.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: kblockd blk_mq_run_work_fn
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