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BUG: KCSAN: data-race in __blk_mq_sched_dispatch_requests / blk_mq_dispatch_rq_list

write to 0xffff888100333ef8 of 4 bytes by task 239 on cpu 1:
 blk_mq_dispatch_rq_list+0xfa7/0x11b0
 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:170 [inline]
 blk_mq_do_dispatch_sched block/blk-mq-sched.c:184 [inline]
 __blk_mq_sched_dispatch_requests+0x69a/0xdd0 block/blk-mq-sched.c:309
 blk_mq_sched_dispatch_requests+0x99/0x100 block/blk-mq-sched.c:333
 blk_mq_run_work_fn+0x65/0xe0 block/blk-mq.c:2406
 process_one_work+0x434/0x860 kernel/workqueue.c:2597
 worker_thread+0x5f2/0xa10 kernel/workqueue.c:2748
 kthread+0x1d7/0x210 kernel/kthread.c:389
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

read to 0xffff888100333ef8 of 4 bytes by task 23196 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+0x99/0x100 block/blk-mq-sched.c:333
 blk_mq_run_hw_queue+0x29c/0x4c0 block/blk-mq.c:2237
 blk_mq_get_tag+0x479/0x590 block/blk-mq-tag.c:170
 __blk_mq_alloc_requests+0x5db/0x720 block/blk-mq.c:488
 blk_mq_get_new_requests block/blk-mq.c:2855 [inline]
 blk_mq_submit_bio+0x46e/0xcd0 block/blk-mq.c:2951
 __submit_bio+0x11c/0x350 block/blk-core.c:598
 __submit_bio_noacct_mq block/blk-core.c:677 [inline]
 submit_bio_noacct_nocheck+0x4ad/0x5e0 block/blk-core.c:706
 submit_bio_noacct+0x75c/0x900 block/blk-core.c:805
 submit_bio+0xb7/0xc0 block/blk-core.c:838
 ext4_io_submit fs/ext4/page-io.c:378 [inline]
 io_submit_add_bh fs/ext4/page-io.c:419 [inline]
 ext4_bio_write_folio+0x65f/0x8d0 fs/ext4/page-io.c:563
 mpage_submit_folio fs/ext4/inode.c:1865 [inline]
 mpage_map_and_submit_buffers fs/ext4/inode.c:2111 [inline]
 mpage_map_and_submit_extent fs/ext4/inode.c:2251 [inline]
 ext4_do_writepages+0x1416/0x21e0 fs/ext4/inode.c:2677
 ext4_writepages+0x15e/0x2e0 fs/ext4/inode.c:2766
 do_writepages+0x1c5/0x340 mm/page-writeback.c:2551
 __writeback_single_inode+0x91/0x860 fs/fs-writeback.c:1603
 writeback_sb_inodes+0x511/0xaa0 fs/fs-writeback.c:1894
 wb_writeback+0x252/0x6e0 fs/fs-writeback.c:2070
 wb_do_writeback fs/fs-writeback.c:2217 [inline]
 wb_workfn+0x1a8/0x8d0 fs/fs-writeback.c:2257
 process_one_work+0x434/0x860 kernel/workqueue.c:2597
 worker_thread+0x5f2/0xa10 kernel/workqueue.c:2748
 kthread+0x1d7/0x210 kernel/kthread.c:389
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

value changed: 0x00000007 -> 0x00000008

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 23196 Comm: kworker/u4:1 Not tainted 6.4.0-syzkaller-11478-gd528014517f2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Workqueue: writeback wb_workfn (flush-8:0)
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