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BUG: KCSAN: data-race in __blk_mq_sched_dispatch_requests / blk_mq_dispatch_rq_list

write to 0xffff8881001966f8 of 4 bytes by task 12170 on cpu 0:
 blk_mq_dispatch_rq_list+0xfd6/0x11f0
 __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_hw_queue+0x29c/0x4c0 block/blk-mq.c:2266
 blk_mq_get_tag+0x479/0x590 block/blk-mq-tag.c:170
 __blk_mq_alloc_requests+0x5b9/0x850 block/blk-mq.c:498
 blk_mq_get_new_requests block/blk-mq.c:2891 [inline]
 blk_mq_submit_bio+0x46e/0xd70 block/blk-mq.c:2988
 __submit_bio+0x11c/0x350 block/blk-core.c:598
 __submit_bio_noacct_mq block/blk-core.c:677 [inline]
 submit_bio_noacct_nocheck+0x449/0x5e0 block/blk-core.c:706
 submit_bio_noacct+0x700/0x8a0 block/blk-core.c:800
 submit_bio+0xb7/0xc0 block/blk-core.c:833
 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:2553
 filemap_fdatawrite_wbc+0xdb/0xf0 mm/filemap.c:393
 __filemap_fdatawrite_range mm/filemap.c:426 [inline]
 __filemap_fdatawrite mm/filemap.c:432 [inline]
 filemap_flush+0x95/0xc0 mm/filemap.c:459
 ext4_alloc_da_blocks+0x50/0x130 fs/ext4/inode.c:3033
 ext4_release_file+0x5f/0x1c0 fs/ext4/file.c:169
 __fput+0x2fd/0x600 fs/file_table.c:384
 ____fput+0x15/0x20 fs/file_table.c:412
 task_work_run+0x135/0x1a0 kernel/task_work.c:179
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0x5ff/0x1670 kernel/exit.c:874
 do_group_exit+0x101/0x150 kernel/exit.c:1024
 get_signal+0xeb7/0xff0 kernel/signal.c:2881
 arch_do_signal_or_restart+0x89/0x2a0 arch/x86/kernel/signal.c:308
 exit_to_user_mode_loop+0x6f/0xe0 kernel/entry/common.c:168
 exit_to_user_mode_prepare+0x6c/0xb0 kernel/entry/common.c:204
 irqentry_exit_to_user_mode+0x9/0x20 kernel/entry/common.c:310
 irqentry_exit+0x12/0x40 kernel/entry/common.c:413
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570

read to 0xffff8881001966f8 of 4 bytes by task 74 on cpu 1:
 __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_work_fn+0x65/0xe0 block/blk-mq.c:2435
 process_one_work+0x434/0x860 kernel/workqueue.c:2600
 worker_thread+0x5f2/0xa10 kernel/workqueue.c:2751
 kthread+0x1d7/0x210 kernel/kthread.c:389
 ret_from_fork+0x2e/0x40 arch/x86/kernel/process.c:145
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304

value changed: 0x00000003 -> 0x00000004

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 74 Comm: kworker/1:1H Tainted: G        W          6.5.0-rc7-syzkaller-00004-gf7757129e3de #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Workqueue: kblockd blk_mq_run_work_fn
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