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BUG: KCSAN: data-race in dd_has_work / deadline_remove_request

write to 0xffff888100921090 of 8 bytes by task 6673 on cpu 0:
 __list_del include/linux/list.h:112 [inline]
 __list_del_entry include/linux/list.h:135 [inline]
 list_del_init include/linux/list.h:204 [inline]
 deadline_remove_request+0x58/0x180 block/mq-deadline-main.c:198
 deadline_move_request block/mq-deadline-main.c:274 [inline]
 __dd_dispatch_request+0x3d3/0x4b0 block/mq-deadline-main.c:472
 dd_dispatch_request+0x138/0x1e0 block/mq-deadline-main.c:518
 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:149 [inline]
 blk_mq_do_dispatch_sched+0x1e4/0x640 block/blk-mq-sched.c:214
 __blk_mq_sched_dispatch_requests+0x1eb/0x290 block/blk-mq-sched.c:329
 blk_mq_sched_dispatch_requests+0x9f/0x110 block/blk-mq-sched.c:360
 __blk_mq_run_hw_queue+0xbc/0x140 block/blk-mq.c:1500
 __blk_mq_delay_run_hw_queue+0x163/0x2f0 block/blk-mq.c:1577
 blk_mq_run_hw_queue+0x22c/0x250 block/blk-mq.c:1630
 blk_mq_sched_insert_requests+0x12b/0x1f0 block/blk-mq-sched.c:513
 blk_mq_flush_plug_list+0x2f2/0x3c0 block/blk-mq.c:1955
 blk_flush_plug_list+0x235/0x260 block/blk-core.c:1733
 blk_mq_submit_bio+0x687/0xe80 block/blk-mq.c:2256
 __submit_bio_noacct_mq block/blk-core.c:1013 [inline]
 submit_bio_noacct+0x6f2/0x7e0 block/blk-core.c:1046
 submit_bio+0x10c/0x190 include/linux/vmstat.h:81
 ext4_io_submit+0xcd/0xf0 fs/ext4/page-io.c:379
 ext4_writepages+0xaea/0x1d10 fs/ext4/inode.c:2820
 do_writepages+0x7b/0x150 mm/page-writeback.c:2355
 __filemap_fdatawrite_range mm/filemap.c:413 [inline]
 __filemap_fdatawrite mm/filemap.c:421 [inline]
 filemap_flush+0x132/0x160 mm/filemap.c:448
 ext4_alloc_da_blocks+0x47/0xd0 fs/ext4/inode.c:3164
 ext4_release_file+0x5b/0x1d0 fs/ext4/file.c:141
 __fput+0x25b/0x4e0 fs/file_table.c:280
 ____fput+0x11/0x20 fs/file_table.c:313
 task_work_run+0xae/0x130 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
 exit_to_user_mode_prepare+0x156/0x190 kernel/entry/common.c:209
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:302
 do_syscall_64+0x49/0x90 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888100921090 of 8 bytes by task 6671 on cpu 1:
 list_empty_careful include/linux/list.h:319 [inline]
 dd_has_work_for_prio block/mq-deadline-main.c:841 [inline]
 dd_has_work+0x187/0x260 block/mq-deadline-main.c:850
 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:137 [inline]
 blk_mq_do_dispatch_sched+0x12a/0x640 block/blk-mq-sched.c:214
 __blk_mq_sched_dispatch_requests+0x1eb/0x290 block/blk-mq-sched.c:329
 blk_mq_sched_dispatch_requests+0x9f/0x110 block/blk-mq-sched.c:360
 __blk_mq_run_hw_queue+0xbc/0x140 block/blk-mq.c:1500
 __blk_mq_delay_run_hw_queue+0x163/0x2f0 block/blk-mq.c:1577
 blk_mq_run_hw_queue+0x22c/0x250 block/blk-mq.c:1630
 blk_mq_sched_insert_requests+0x12b/0x1f0 block/blk-mq-sched.c:513
 blk_mq_flush_plug_list+0x2f2/0x3c0 block/blk-mq.c:1955
 blk_flush_plug_list+0x235/0x260 block/blk-core.c:1733
 blk_mq_submit_bio+0x687/0xe80 block/blk-mq.c:2256
 __submit_bio_noacct_mq block/blk-core.c:1013 [inline]
 submit_bio_noacct+0x6f2/0x7e0 block/blk-core.c:1046
 submit_bio+0x10c/0x190 include/linux/vmstat.h:81
 ext4_io_submit+0xcd/0xf0 fs/ext4/page-io.c:379
 ext4_writepages+0xaea/0x1d10 fs/ext4/inode.c:2820
 do_writepages+0x7b/0x150 mm/page-writeback.c:2355
 __filemap_fdatawrite_range mm/filemap.c:413 [inline]
 __filemap_fdatawrite mm/filemap.c:421 [inline]
 filemap_flush+0x132/0x160 mm/filemap.c:448
 ext4_alloc_da_blocks+0x47/0xd0 fs/ext4/inode.c:3164
 ext4_release_file+0x5b/0x1d0 fs/ext4/file.c:141
 __fput+0x25b/0x4e0 fs/file_table.c:280
 ____fput+0x11/0x20 fs/file_table.c:313
 task_work_run+0xae/0x130 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
 exit_to_user_mode_prepare+0x156/0x190 kernel/entry/common.c:209
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:302
 do_syscall_64+0x49/0x90 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0xffff888102b970c8 -> 0xffff888100921088

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 6671 Comm: syz-executor.4 Not tainted 5.13.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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