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BUG: KCSAN: data-race in blk_mq_dispatch_rq_list / blk_mq_dispatch_rq_list

read to 0xffff8881026e2168 of 8 bytes by task 9621 on cpu 0:
 blk_mq_dispatch_rq_list+0xab7/0x1070 block/blk-mq.c:1397
 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:201 [inline]
 blk_mq_do_dispatch_sched+0x3b5/0x640 block/blk-mq-sched.c:214
 __blk_mq_sched_dispatch_requests+0x1eb/0x290
 blk_mq_sched_dispatch_requests+0x9f/0x110 block/blk-mq-sched.c:360
 __blk_mq_run_hw_queue+0xbc/0x140 block/blk-mq.c:1492
 __blk_mq_delay_run_hw_queue+0x163/0x2f0 block/blk-mq.c:1569
 blk_mq_run_hw_queue+0x22c/0x250 block/blk-mq.c:1622
 blk_mq_sched_insert_requests+0x12b/0x1f0 block/blk-mq-sched.c:513
 blk_mq_flush_plug_list+0x302/0x3d0 block/blk-mq.c:1947
 blk_flush_plug_list+0x235/0x260 block/blk-core.c:1726
 blk_finish_plug+0x44/0x60 block/blk-core.c:1743
 __iomap_dio_rw+0xca7/0x1010 fs/iomap/direct-io.c:570
 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

write to 0xffff8881026e2168 of 8 bytes by task 9683 on cpu 1:
 blk_mq_dispatch_rq_list+0xaca/0x1070 block/blk-mq.c:1397
 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:201 [inline]
 blk_mq_do_dispatch_sched+0x3b5/0x640 block/blk-mq-sched.c:214
 __blk_mq_sched_dispatch_requests+0x1eb/0x290
 blk_mq_sched_dispatch_requests+0x9f/0x110 block/blk-mq-sched.c:360
 __blk_mq_run_hw_queue+0xbc/0x140 block/blk-mq.c:1492
 __blk_mq_delay_run_hw_queue+0x163/0x2f0 block/blk-mq.c:1569
 blk_mq_run_hw_queue+0x22c/0x250 block/blk-mq.c:1622
 blk_mq_sched_insert_requests+0x12b/0x1f0 block/blk-mq-sched.c:513
 blk_mq_flush_plug_list+0x302/0x3d0 block/blk-mq.c:1947
 blk_flush_plug_list+0x235/0x260 block/blk-core.c:1726
 blk_finish_plug+0x44/0x60 block/blk-core.c:1743
 __iomap_dio_rw+0xca7/0x1010 fs/iomap/direct-io.c:570
 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: 0x000000000000f955 -> 0x000000000000f956

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 9683 Comm: syz-executor.2 Not tainted 5.15.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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