syzbot

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BUG: KCSAN: data-race in blk_mq_sched_dispatch_requests / blk_mq_sched_dispatch_requests

write to 0xffff888129a99150 of 8 bytes by task 7180 on cpu 0:
 blk_mq_sched_dispatch_requests+0x118/0x380 block/blk-mq-sched.c:181
 __blk_mq_run_hw_queue+0xb7/0x160 block/blk-mq.c:1387
 __blk_mq_delay_run_hw_queue+0x31b/0x3a0 block/blk-mq.c:1455
 blk_mq_run_hw_queue+0x103/0x1c0 block/blk-mq.c:1492
 blk_mq_sched_insert_requests+0x1ca/0x2e0 block/blk-mq-sched.c:444
 blk_mq_flush_plug_list+0x572/0x6c0 block/blk-mq.c:1756
 blk_flush_plug_list+0x271/0x2a0 block/blk-core.c:1728
 blk_mq_make_request+0x65e/0xf40 block/blk-mq.c:1994
 generic_make_request block/blk-core.c:1052 [inline]
 generic_make_request+0x196/0x740 block/blk-core.c:994
 submit_bio+0x92/0x310 block/blk-core.c:1163
 dio_bio_submit fs/direct-io.c:482 [inline]
 do_blockdev_direct_IO+0x2a97/0x4cc0 fs/direct-io.c:1354
 __blockdev_direct_IO+0x86/0xa0 fs/direct-io.c:1413
 ext4_direct_IO_write fs/ext4/inode.c:3788 [inline]
 ext4_direct_IO+0x6f5/0xf70 fs/ext4/inode.c:3915
 generic_file_direct_write+0x14d/0x2e0 mm/filemap.c:3230

read to 0xffff888129a99150 of 8 bytes by task 2509 on cpu 1:
 blk_mq_sched_dispatch_requests+0x104/0x380 block/blk-mq-sched.c:181
 __blk_mq_run_hw_queue+0xb7/0x160 block/blk-mq.c:1387
 blk_mq_run_work_fn+0x57/0x70 block/blk-mq.c:1620
 process_one_work+0x3d4/0x890 kernel/workqueue.c:2269
 worker_thread+0xa0/0x800 kernel/workqueue.c:2415
 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 2509 Comm: kworker/1:1H Not tainted 5.3.0+ #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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