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BUG: KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert

write to 0xffff8881020bec10 of 8 bytes by task 227 on cpu 1:
 __list_add include/linux/list.h:72 [inline]
 list_add include/linux/list.h:88 [inline]
 blk_mq_request_bypass_insert+0x6a/0x130 block/blk-mq.c:2345
 blk_mq_sched_insert_request+0xfd/0x220 block/blk-mq-sched.c:434
 blk_mq_requeue_work+0x38b/0x3f0 block/blk-mq.c:1306
 process_one_work+0x3f6/0x960 kernel/workqueue.c:2307
 worker_thread+0x616/0xa70 kernel/workqueue.c:2454
 kthread+0x1bf/0x1e0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30

read to 0xffff8881020bec10 of 8 bytes by task 1835 on cpu 0:
 list_empty_careful include/linux/list.h:329 [inline]
 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:112 [inline]
 blk_mq_do_dispatch_sched+0x167/0x6d0 block/blk-mq-sched.c:186
 __blk_mq_sched_dispatch_requests+0x1ca/0x270
 blk_mq_sched_dispatch_requests+0x9f/0x110 block/blk-mq-sched.c:332
 __blk_mq_run_hw_queue+0x7e/0x100 block/blk-mq.c:1968
 __blk_mq_delay_run_hw_queue+0x19c/0x390 block/blk-mq.c:2045
 blk_mq_run_hw_queue+0x180/0x310 block/blk-mq.c:2096
 blk_mq_sched_insert_requests+0x1cc/0x2a0 block/blk-mq-sched.c:486
 blk_mq_flush_plug_list+0x5c3/0x6c0 block/blk-mq.c:2628
 blk_flush_plug+0x25a/0x2b0 block/blk-core.c:1269
 blk_finish_plug+0x44/0x60 block/blk-core.c:1293
 __iomap_dio_rw+0xcd4/0x10b0 fs/iomap/direct-io.c:598
 iomap_dio_rw+0x38/0x80 fs/iomap/direct-io.c:680
 ext4_dio_read_iter fs/ext4/file.c:77 [inline]
 ext4_file_read_iter+0x190/0x1f0 fs/ext4/file.c:128
 call_read_iter include/linux/fs.h:2068 [inline]
 lo_rw_aio+0x604/0x7d0 drivers/block/loop.c:453
 loop_handle_cmd drivers/block/loop.c:1853 [inline]
 loop_process_work+0x3bf/0x12d0 drivers/block/loop.c:1893
 loop_rootcg_workfn+0x1b/0x20 drivers/block/loop.c:1924
 process_one_work+0x3f6/0x960 kernel/workqueue.c:2307
 worker_thread+0x616/0xa70 kernel/workqueue.c:2454
 kthread+0x1bf/0x1e0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30

value changed: 0xffff8881020bec08 -> 0xffff88810184dc48

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 1835 Comm: kworker/u4:4 Not tainted 5.17.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: loop4 loop_rootcg_workfn
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