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BUG: KCSAN: data-race in dd_has_work / dd_insert_request

write to 0xffff888102639688 of 8 bytes by task 840 on cpu 1:
 __list_add include/linux/list.h:72 [inline]
 list_add_tail include/linux/list.h:102 [inline]
 dd_insert_request+0x415/0x550 block/mq-deadline.c:758
 dd_insert_requests+0xfc/0x140 block/mq-deadline.c:777
 blk_mq_sched_insert_request+0x203/0x220 block/blk-mq-sched.c:449
 blk_mq_submit_bio+0xba1/0xe40 block/blk-mq.c:2853
 __submit_bio+0x130/0x330 block/blk-core.c:662
 __submit_bio_noacct_mq block/blk-core.c:739 [inline]
 submit_bio_noacct_nocheck+0x3cb/0x480 block/blk-core.c:756
 submit_bio_noacct+0x6c4/0x820 block/blk-core.c:863
 submit_bio+0x139/0x150
 ext4_mpage_readpages+0xff5/0x1040 fs/ext4/readpage.c:405
 filemap_read_folio mm/filemap.c:2422 [inline]
 filemap_create_folio mm/filemap.c:2547 [inline]
 filemap_get_pages mm/filemap.c:2599 [inline]
 filemap_read+0x9b4/0x1400 mm/filemap.c:2679
 generic_file_read_iter+0x72/0x320 mm/filemap.c:2825
 call_read_iter include/linux/fs.h:2044 [inline]
 generic_file_splice_read+0x1de/0x2c0 fs/splice.c:311
 do_splice_to fs/splice.c:796 [inline]
 splice_direct_to_actor+0x2ac/0x660 fs/splice.c:870
 do_splice_direct+0xfb/0x180 fs/splice.c:979
 do_sendfile+0x3ad/0x900 fs/read_write.c:1246
 __do_sys_sendfile64 fs/read_write.c:1311 [inline]
 __se_sys_sendfile64 fs/read_write.c:1297 [inline]
 __x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1297
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888102639688 of 8 bytes by task 9 on cpu 0:
 list_empty_careful include/linux/list.h:329 [inline]
 dd_has_work_for_prio block/mq-deadline.c:836 [inline]
 dd_has_work+0x144/0x260 block/mq-deadline.c:846
 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:109 [inline]
 blk_mq_do_dispatch_sched+0x148/0x780 block/blk-mq-sched.c:187
 __blk_mq_sched_dispatch_requests+0x1ca/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:1974
 blk_mq_run_work_fn+0x3d/0x50 block/blk-mq.c:2312
 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

value changed: 0xffff888102639680 -> 0xffff888103195808

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 9 Comm: kworker/0:1H Tainted: G        W         5.18.0-rc7-syzkaller-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: kblockd blk_mq_run_work_fn
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