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BUG: KCSAN: data-race in __blk_mq_sched_dispatch_requests / blk_mq_request_bypass_insert

write to 0xffff888101c49410 of 8 bytes by task 315 on cpu 0:
 __list_add include/linux/list.h:70 [inline]
 list_add include/linux/list.h:86 [inline]
 blk_mq_request_bypass_insert+0x6a/0x150 block/blk-mq.c:1859
 blk_mq_sched_insert_request+0xfc/0x250 block/blk-mq-sched.c:462
 blk_mq_requeue_work+0x3cb/0x440 block/blk-mq.c:795
 process_one_work+0x402/0x910 kernel/workqueue.c:2297
 worker_thread+0x636/0xae0 kernel/workqueue.c:2444
 kthread+0x262/0x280 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30

read to 0xffff888101c49410 of 8 bytes by task 32358 on cpu 1:
 list_empty_careful include/linux/list.h:319 [inline]
 __blk_mq_sched_dispatch_requests+0x80/0x290 block/blk-mq-sched.c:305
 blk_mq_sched_dispatch_requests+0x9f/0x110 block/blk-mq-sched.c:360
 __blk_mq_run_hw_queue+0xbc/0x140 block/blk-mq.c:1480
 __blk_mq_delay_run_hw_queue+0x163/0x2f0 block/blk-mq.c:1557
 blk_mq_run_hw_queue+0x22c/0x250 block/blk-mq.c:1610
 blk_mq_sched_insert_requests+0x12b/0x1f0 block/blk-mq-sched.c:513
 blk_mq_flush_plug_list+0x302/0x3d0 block/blk-mq.c:1935
 blk_flush_plug_list+0x235/0x260 block/blk-core.c:1718
 blk_finish_plug+0x44/0x60 block/blk-core.c:1735
 ext4_writepages+0x18f1/0x1d70 fs/ext4/inode.c:2849
 do_writepages+0x26b/0x3c0 mm/page-writeback.c:2364
 filemap_fdatawrite_wbc mm/filemap.c:400 [inline]
 __filemap_fdatawrite_range mm/filemap.c:433 [inline]
 filemap_write_and_wait_range+0x238/0x3c0 mm/filemap.c:704
 __iomap_dio_rw+0x4ca/0x1010 fs/iomap/direct-io.c:540
 iomap_dio_rw+0x30/0x70 fs/iomap/direct-io.c:649
 ext4_dio_read_iter fs/ext4/file.c:77 [inline]
 ext4_file_read_iter+0x21a/0x290 fs/ext4/file.c:128
 call_read_iter include/linux/fs.h:2157 [inline]
 generic_file_splice_read+0x24f/0x330 fs/splice.c:311
 do_splice_to fs/splice.c:796 [inline]
 splice_direct_to_actor+0x2aa/0x650 fs/splice.c:870
 do_splice_direct+0x106/0x190 fs/splice.c:979
 do_sendfile+0x63e/0xbb0 fs/read_write.c:1249
 __do_sys_sendfile64 fs/read_write.c:1314 [inline]
 __se_sys_sendfile64 fs/read_write.c:1300 [inline]
 __x64_sys_sendfile64+0x102/0x140 fs/read_write.c:1300
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0xffff888101c49408 -> 0xffff888101c49048

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 32358 Comm: syz-executor.4 Not tainted 5.15.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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