syzbot

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BUG: KCSAN: data-race in rq_qos_wait / rq_qos_wake_function

write to 0xffff88821aaa9d90 of 8 bytes by interrupt on cpu 1:
 __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]
 rq_qos_wake_function block/blk-rq-qos.c:228 [inline]
 rq_qos_wake_function+0x14d/0x180 block/blk-rq-qos.c:212
 __wake_up_common+0x7b/0x180 kernel/sched/wait.c:93
 __wake_up_common_lock+0x77/0xb0 kernel/sched/wait.c:123
 __wake_up+0xe/0x10 kernel/sched/wait.c:142
 wbt_rqw_done+0x188/0x230 block/blk-wbt.c:165
 __wbt_done+0x7f/0xc0 block/blk-wbt.c:178
 wbt_done+0x15d/0x1b0 block/blk-wbt.c:199
 __rq_qos_done+0x4a/0x80 block/blk-rq-qos.c:45
 rq_qos_done block/blk-rq-qos.h:153 [inline]
 blk_mq_free_request+0x24c/0x360 block/blk-mq.c:510
 __blk_mq_end_request block/blk-mq.c:539 [inline]
 blk_mq_end_request+0x2e0/0x300 block/blk-mq.c:548
 end_cmd drivers/block/null_blk_main.c:648 [inline]
 end_cmd+0xa9/0x1a0 drivers/block/null_blk_main.c:642
 null_complete_rq+0x22/0x30 drivers/block/null_blk_main.c:675
 blk_done_softirq+0x1eb/0x250 block/blk-softirq.c:37
 __do_softirq+0x115/0x33f kernel/softirq.c:292
 run_ksoftirqd+0x46/0x60 kernel/softirq.c:603
 smpboot_thread_fn+0x37d/0x4a0 kernel/smpboot.c:165
 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

read to 0xffff88821aaa9d90 of 8 bytes by task 9227 on cpu 0:
 list_is_singular include/linux/list.h:342 [inline]
 wq_has_single_sleeper include/linux/wait.h:139 [inline]
 rq_qos_wait+0x15c/0x320 block/blk-rq-qos.c:270
 __wbt_wait block/blk-wbt.c:526 [inline]
 wbt_wait+0x161/0x260 block/blk-wbt.c:591
 __rq_qos_throttle+0x47/0x70 block/blk-rq-qos.c:72
 rq_qos_throttle block/blk-rq-qos.h:182 [inline]
 blk_mq_make_request+0x29c/0xf60 block/blk-mq.c:1984
 generic_make_request block/blk-core.c:1069 [inline]
 generic_make_request+0x196/0x700 block/blk-core.c:1011
 submit_bio+0x96/0x3b0 block/blk-core.c:1195
 blk_next_bio+0x53/0x70 block/blk-lib.c:19
 __blkdev_issue_zero_pages+0x104/0x300 block/blk-lib.c:284
 blkdev_issue_zeroout+0x32d/0x360 block/blk-lib.c:378
 blk_ioctl_zeroout block/ioctl.c:269 [inline]
 blkdev_common_ioctl+0x44f/0xeb0 block/ioctl.c:607
 blkdev_ioctl+0x12e/0x400 block/ioctl.c:715
 block_ioctl+0x95/0xc0 fs/block_dev.c:1983
 vfs_ioctl fs/ioctl.c:47 [inline]
 ksys_ioctl+0x109/0x150 fs/ioctl.c:763
 __do_sys_ioctl fs/ioctl.c:772 [inline]
 __se_sys_ioctl fs/ioctl.c:770 [inline]
 __x64_sys_ioctl+0x4c/0x60 fs/ioctl.c:770
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 9227 Comm: syz-executor.3 Not tainted 5.6.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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