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BUG: KCSAN: data-race in __blk_mq_sched_dispatch_requests / blk_mq_dispatch_rq_list

write to 0xffff8881029048f8 of 4 bytes by task 73 on cpu 1:
 blk_mq_dispatch_rq_list+0xfa7/0x11b0
 __blk_mq_sched_dispatch_requests+0x1d4/0xdd0 block/blk-mq-sched.c:301
 blk_mq_sched_dispatch_requests+0x93/0x100 block/blk-mq-sched.c:333
 blk_mq_run_work_fn+0x65/0xe0 block/blk-mq.c:2418
 process_one_work+0x3e6/0x750 kernel/workqueue.c:2405
 worker_thread+0x5f2/0xa10 kernel/workqueue.c:2552
 kthread+0x1d7/0x210 kernel/kthread.c:379
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

read to 0xffff8881029048f8 of 4 bytes by task 9021 on cpu 0:
 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:97 [inline]
 blk_mq_do_dispatch_sched block/blk-mq-sched.c:184 [inline]
 __blk_mq_sched_dispatch_requests+0x29b/0xdd0 block/blk-mq-sched.c:309
 blk_mq_sched_dispatch_requests+0x93/0x100 block/blk-mq-sched.c:333
 blk_mq_run_hw_queue+0x290/0x4b0 block/blk-mq.c:2249
 blk_mq_get_tag+0x479/0x590 block/blk-mq-tag.c:161
 __blk_mq_alloc_requests+0x5a8/0x6d0 block/blk-mq.c:492
 blk_mq_get_new_requests block/blk-mq.c:2858 [inline]
 blk_mq_submit_bio+0x4a1/0xe40 block/blk-mq.c:2954
 __submit_bio+0x116/0x350 block/blk-core.c:594
 __submit_bio_noacct_mq block/blk-core.c:673 [inline]
 submit_bio_noacct_nocheck+0x4ad/0x5e0 block/blk-core.c:702
 submit_bio_noacct+0x75d/0x8f0 block/blk-core.c:801
 submit_bio+0xb7/0xc0 block/blk-core.c:834
 iomap_dio_submit_bio fs/iomap/direct-io.c:77 [inline]
 iomap_dio_bio_iter+0x94e/0xaf0 fs/iomap/direct-io.c:355
 __iomap_dio_rw+0x984/0x1100 fs/iomap/direct-io.c:598
 iomap_dio_rw+0x40/0x90 fs/iomap/direct-io.c:688
 ext4_dio_write_iter fs/ext4/file.c:597 [inline]
 ext4_file_write_iter+0x9e6/0x10e0 fs/ext4/file.c:708
 call_write_iter include/linux/fs.h:1868 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x47b/0x780 fs/read_write.c:584
 ksys_write+0xeb/0x1a0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x42/0x50 fs/read_write.c:646
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00000008 -> 0x00000007

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 9021 Comm: syz-executor.2 Not tainted 6.4.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023
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