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BUG: KCSAN: data-race in blk_mq_dispatch_rq_list / blk_mq_do_dispatch_sched

write to 0xffff888101f98cf8 of 4 bytes by task 41 on cpu 1:
 blk_mq_update_dispatch_busy block/blk-mq.c:1848 [inline]
 blk_mq_dispatch_rq_list+0x1131/0x1250 block/blk-mq.c:2088
 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:173 [inline]
 blk_mq_do_dispatch_sched+0x49d/0x7f0 block/blk-mq-sched.c:187
 __blk_mq_sched_dispatch_requests+0x1cd/0x270
 blk_mq_sched_dispatch_requests+0x8f/0xf0 block/blk-mq-sched.c:339
 __blk_mq_run_hw_queue+0x7e/0x100 block/blk-mq.c:2110
 blk_mq_run_work_fn+0x3d/0x50 block/blk-mq.c:2409
 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289
 worker_thread+0x618/0xa70 kernel/workqueue.c:2436
 kthread+0x1a9/0x1e0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306

read to 0xffff888101f98cf8 of 4 bytes by task 8 on cpu 0:
 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:100 [inline]
 blk_mq_do_dispatch_sched+0xc9/0x7f0 block/blk-mq-sched.c:187
 __blk_mq_sched_dispatch_requests+0x1cd/0x270
 blk_mq_sched_dispatch_requests+0x8f/0xf0 block/blk-mq-sched.c:339
 __blk_mq_run_hw_queue+0x7e/0x100 block/blk-mq.c:2110
 __blk_mq_delay_run_hw_queue+0x15b/0x2e0 block/blk-mq.c:2186
 blk_mq_run_hw_queue+0x180/0x320 block/blk-mq.c:2234
 blk_mq_get_tag+0x456/0x570 block/blk-mq-tag.c:163
 __blk_mq_alloc_requests+0x5f0/0x710 block/blk-mq.c:495
 blk_mq_get_new_requests block/blk-mq.c:2814 [inline]
 blk_mq_submit_bio+0x456/0xe90 block/blk-mq.c:2902
 __submit_bio block/blk-core.c:591 [inline]
 __submit_bio_noacct_mq block/blk-core.c:668 [inline]
 submit_bio_noacct_nocheck+0x83d/0xaa0 block/blk-core.c:685
 submit_bio_noacct+0x6a5/0x810 block/blk-core.c:791
 submit_bio+0xfb/0x110 block/blk-core.c:827
 ext4_io_submit fs/ext4/page-io.c:378 [inline]
 io_submit_add_bh fs/ext4/page-io.c:420 [inline]
 ext4_bio_write_page+0x5cd/0xb60 fs/ext4/page-io.c:546
 mpage_submit_page fs/ext4/inode.c:2121 [inline]
 mpage_map_and_submit_buffers fs/ext4/inode.c:2366 [inline]
 mpage_map_and_submit_extent fs/ext4/inode.c:2505 [inline]
 ext4_writepages+0x1020/0x1cf0 fs/ext4/inode.c:2834
 do_writepages+0x1db/0x350 mm/page-writeback.c:2469
 __writeback_single_inode+0x81/0x590 fs/fs-writeback.c:1587
 writeback_sb_inodes+0x6a0/0xdd0 fs/fs-writeback.c:1870
 wb_writeback+0x26b/0x650 fs/fs-writeback.c:2044
 wb_do_writeback+0x101/0x600 fs/fs-writeback.c:2187
 wb_workfn+0x88/0x260 fs/fs-writeback.c:2227
 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289
 worker_thread+0x618/0xa70 kernel/workqueue.c:2436
 kthread+0x1a9/0x1e0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306

value changed: 0x00000007 -> 0x00000008

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 8 Comm: kworker/u4:0 Not tainted 6.1.0-rc3-syzkaller-00299-g2f5065a0bc9d-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Workqueue: writeback wb_workfn (flush-8:0)
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