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BUG: KCSAN: data-race in __blk_mq_sched_dispatch_requests / blk_mq_dispatch_rq_list

write to 0xffff888100c0b8f8 of 4 bytes by task 43 on cpu 1:
 blk_mq_dispatch_rq_list+0xf4d/0x1090
 __blk_mq_sched_dispatch_requests+0x1ce/0xd20 block/blk-mq-sched.c:301
 blk_mq_sched_dispatch_requests+0x99/0x100 block/blk-mq-sched.c:333
 blk_mq_run_work_fn+0x65/0xe0 block/blk-mq.c:2434
 process_one_work kernel/workqueue.c:2627 [inline]
 process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2700
 worker_thread+0x525/0x730 kernel/workqueue.c:2781
 kthread+0x1d7/0x210 kernel/kthread.c:388
 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

read to 0xffff888100c0b8f8 of 4 bytes by task 8035 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+0x28b/0xd20 block/blk-mq-sched.c:309
 blk_mq_sched_dispatch_requests+0x99/0x100 block/blk-mq-sched.c:333
 blk_mq_run_hw_queue+0x2a4/0x4c0 block/blk-mq.c:2264
 blk_mq_get_tag+0x479/0x590 block/blk-mq-tag.c:170
 __blk_mq_alloc_requests+0x642/0x9e0 block/blk-mq.c:501
 blk_mq_get_new_requests block/blk-mq.c:2884 [inline]
 blk_mq_submit_bio+0x468/0xd90 block/blk-mq.c:2982
 __submit_bio+0x11c/0x350 block/blk-core.c:607
 __submit_bio_noacct_mq block/blk-core.c:686 [inline]
 submit_bio_noacct_nocheck+0x4ad/0x5e0 block/blk-core.c:715
 submit_bio_noacct+0x70c/0x8c0 block/blk-core.c:809
 submit_bio+0xb7/0xc0 block/blk-core.c:842
 ext4_io_submit+0x8a/0xa0 fs/ext4/page-io.c:378
 ext4_do_writepages+0xb3a/0x2100 fs/ext4/inode.c:2705
 ext4_writepages+0x15e/0x2e0 fs/ext4/inode.c:2774
 do_writepages+0x1c2/0x340 mm/page-writeback.c:2553
 __writeback_single_inode+0x91/0x860 fs/fs-writeback.c:1625
 writeback_sb_inodes+0x514/0xad0 fs/fs-writeback.c:1916
 __writeback_inodes_wb+0x9a/0x1a0 fs/fs-writeback.c:1987
 wb_writeback+0x264/0x6e0 fs/fs-writeback.c:2094
 wb_check_start_all fs/fs-writeback.c:2220 [inline]
 wb_do_writeback fs/fs-writeback.c:2246 [inline]
 wb_workfn+0x4ea/0x8d0 fs/fs-writeback.c:2279
 process_one_work kernel/workqueue.c:2627 [inline]
 process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2700
 worker_thread+0x525/0x730 kernel/workqueue.c:2781
 kthread+0x1d7/0x210 kernel/kthread.c:388
 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

value changed: 0x00000009 -> 0x00000007

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 8035 Comm: kworker/u4:6 Not tainted 6.7.0-rc5-syzkaller-00230-g3b8a9b2e6809 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Workqueue: writeback wb_workfn (flush-8:0)
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