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BUG: KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert

write to 0xffff888101fb3610 of 8 bytes by task 39 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 0xffff888101fb3610 of 8 bytes by task 7766 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
 ext4_writepages+0x1591/0x1a60 fs/ext4/inode.c:2829
 do_writepages+0x1cb/0x330 mm/page-writeback.c:2364
 filemap_fdatawrite_wbc mm/filemap.c:384 [inline]
 __filemap_fdatawrite_range mm/filemap.c:417 [inline]
 file_write_and_wait_range+0x134/0x1d0 mm/filemap.c:775
 ext4_sync_file+0xad/0x570 fs/ext4/fsync.c:151
 vfs_fsync_range+0x107/0x120 fs/sync.c:182
 generic_write_sync include/linux/fs.h:2884 [inline]
 ext4_buffered_write_iter+0x243/0x290 fs/ext4/file.c:275
 ext4_file_write_iter+0x227/0xda0
 call_write_iter include/linux/fs.h:2074 [inline]
 new_sync_write fs/read_write.c:503 [inline]
 vfs_write+0x7f5/0x950 fs/read_write.c:590
 ksys_write+0xd9/0x190 fs/read_write.c:643
 __do_sys_write fs/read_write.c:655 [inline]
 __se_sys_write fs/read_write.c:652 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:652
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0xffff888101fb3608 -> 0xffff88810299c848

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7766 Comm: syz-executor.4 Not tainted 5.17.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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