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BUG: KCSAN: data-race in blk_mq_dispatch_rq_list / blk_mq_dispatch_rq_list

read to 0xffff8881017764f8 of 4 bytes by task 10339 on cpu 0:
 blk_mq_update_dispatch_busy block/blk-mq.c:2000 [inline]
 blk_mq_dispatch_rq_list+0x884/0xef0 block/blk-mq.c:2223
 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:168 [inline]
 blk_mq_do_dispatch_sched block/blk-mq-sched.c:182 [inline]
 __blk_mq_sched_dispatch_requests+0x86c/0xce0 block/blk-mq-sched.c:307
 blk_mq_sched_dispatch_requests+0x86/0x120 block/blk-mq-sched.c:329
 blk_mq_run_hw_queue+0x145/0x1e0 block/blk-mq.c:2370
 blk_mq_get_tag+0x415/0x640 block/blk-mq-tag.c:182
 __blk_mq_alloc_requests+0x801/0xf30 block/blk-mq.c:593
 blk_mq_get_new_requests block/blk-mq.c:3054 [inline]
 blk_mq_submit_bio+0xb52/0x1210 block/blk-mq.c:3188
 __submit_bio+0x54/0x3d0 block/blk-core.c:674
 __submit_bio_noacct_mq block/blk-core.c:757 [inline]
 submit_bio_noacct_nocheck+0x153/0x620 block/blk-core.c:791
 submit_bio_noacct+0x738/0x970 block/blk-core.c:929
 submit_bio+0x2a4/0x2c0 block/blk-core.c:970
 bio_chain_and_submit+0x84/0xb0 block/bio.c:396
 __blkdev_issue_zero_pages+0x1f7/0x240 block/blk-lib.c:215
 blkdev_issue_zero_pages block/blk-lib.c:231 [inline]
 blkdev_issue_zeroout+0x39c/0x4e0 block/blk-lib.c:312
 blk_ioctl_zeroout block/ioctl.c:244 [inline]
 blkdev_common_ioctl+0x1a07/0x2060 block/ioctl.c:667
 blkdev_ioctl+0x31f/0x460 block/ioctl.c:792
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xce/0x140 fs/ioctl.c:583
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:583
 x64_sys_call+0x239d/0x2550 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

write to 0xffff8881017764f8 of 4 bytes by task 430 on cpu 1:
 blk_mq_update_dispatch_busy block/blk-mq.c:2010 [inline]
 blk_mq_dispatch_rq_list+0x8ba/0xef0 block/blk-mq.c:2223
 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:168 [inline]
 blk_mq_do_dispatch_sched block/blk-mq-sched.c:182 [inline]
 __blk_mq_sched_dispatch_requests+0x86c/0xce0 block/blk-mq-sched.c:307
 blk_mq_sched_dispatch_requests+0x86/0x120 block/blk-mq-sched.c:329
 blk_mq_run_hw_queue+0x145/0x1e0 block/blk-mq.c:2370
 blk_mq_run_hw_queues+0x18e/0x270 block/blk-mq.c:2418
 scsi_starved_list_run drivers/scsi/scsi_lib.c:537 [inline]
 scsi_run_queue+0x486/0x590 drivers/scsi/scsi_lib.c:560
 scsi_requeue_run_queue+0x25/0x30 drivers/scsi/scsi_lib.c:573
 process_one_work kernel/workqueue.c:3495 [inline]
 process_scheduled_works+0x53f/0xa20 kernel/workqueue.c:3578
 worker_thread+0x56c/0x770 kernel/workqueue.c:3659
 kthread+0x223/0x270 kernel/kthread.c:436
 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x00000006 -> 0x00000005

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 430 Comm: kworker/1:1H Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/15/2026
Workqueue: kblockd scsi_requeue_run_queue
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