syzbot

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BUG: KCSAN: data-race in rq_qos_wait / rq_qos_wake_function

write to 0xffffc90000f4ba20 of 1 bytes by interrupt on cpu 1:
 rq_qos_wake_function block/blk-rq-qos.c:226 [inline]
 rq_qos_wake_function+0xb0/0x170 block/blk-rq-qos.c:212
 __wake_up_common+0x76/0x180 kernel/sched/wait.c:93
 __wake_up_common_lock+0x77/0xb0 kernel/sched/wait.c:123
 wbt_rqw_done+0x183/0x220 block/blk-wbt.c:165
 __wbt_done+0x7b/0xc0 block/blk-wbt.c:178
 wbt_done+0x14a/0x190 block/blk-wbt.c:199
 __rq_qos_done+0x43/0x70 block/blk-rq-qos.c:45
 rq_qos_done block/blk-rq-qos.h:153 [inline]
 blk_mq_free_request+0x222/0x340 block/blk-mq.c:510
 __blk_mq_end_request block/blk-mq.c:539 [inline]
 blk_mq_end_request+0x2d0/0x2f0 block/blk-mq.c:548
 end_cmd drivers/block/null_blk_main.c:666 [inline]
 end_cmd+0xa2/0x190 drivers/block/null_blk_main.c:660
 null_complete_rq+0x1f/0x30 drivers/block/null_blk_main.c:693
 blk_done_softirq+0x1e6/0x250 block/blk-softirq.c:37
 __do_softirq+0x118/0x34a kernel/softirq.c:292
 run_ksoftirqd+0x41/0x60 kernel/softirq.c:604
 smpboot_thread_fn+0x374/0x4a0 kernel/smpboot.c:165
 kthread+0x203/0x230 kernel/kthread.c:268
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

read to 0xffffc90000f4ba20 of 1 bytes by task 22594 on cpu 0:
 list_is_singular include/linux/list.h:342 [inline]
 wq_has_single_sleeper include/linux/wait.h:140 [inline]
 rq_qos_wait+0x177/0x300 block/blk-rq-qos.c:270
 __wbt_wait block/blk-wbt.c:526 [inline]
 wbt_wait+0x15f/0x260 block/blk-wbt.c:591
 __rq_qos_throttle+0x42/0x70 block/blk-rq-qos.c:72
 rq_qos_throttle block/blk-rq-qos.h:182 [inline]
 blk_mq_make_request+0x297/0xf60 block/blk-mq.c:1998
 generic_make_request block/blk-core.c:1075 [inline]
 generic_make_request+0x196/0x700 block/blk-core.c:1017
 submit_bio+0x8f/0x3a0 block/blk-core.c:1200
 blk_next_bio+0x4f/0x70 block/blk-lib.c:19
 __blkdev_issue_zero_pages+0x106/0x2f0 block/blk-lib.c:284
 blkdev_issue_zeroout+0x32d/0x360 block/blk-lib.c:378
 blk_ioctl_zeroout block/ioctl.c:270 [inline]
 blkdev_common_ioctl+0x44a/0xea0 block/ioctl.c:608
 blkdev_ioctl+0x130/0x420 block/ioctl.c:716
 block_ioctl+0x91/0xb0 fs/block_dev.c:1996
 vfs_ioctl fs/ioctl.c:47 [inline]
 ksys_ioctl+0x101/0x150 fs/ioctl.c:763
 __do_sys_ioctl fs/ioctl.c:772 [inline]
 __se_sys_ioctl fs/ioctl.c:770 [inline]
 __x64_sys_ioctl+0x47/0x60 fs/ioctl.c:770
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 22594 Comm: syz-executor.2 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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