blk-mq: WARN at block/blk-mq.c:585 __blk_mq_run_hw_queue

Sasha Levin
2014-05-07T15:37:59Z

Hi all,

While fuzzing with trinity inside a KVM tools guest running the latest -next
kernel I've stumbled on the following spew:

[ 986.962569] WARNING: CPU: 41 PID: 41607 at block/blk-mq.c:585 __blk_mq_run_hw_queue+0x90/0x500()
[ 986.964364] Modules linked in:
[ 986.964996] CPU: 41 PID: 41607 Comm: kworker/u147:1 Not tainted 3.15.0-rc4-next-20140506-sasha-00021-gc164334-dirty #447
[ 986.967025] Workqueue: kblockd blk_mq_run_work_fn
[ 986.967939] 0000000000000009 ffff8802410e1c68 ffffffff94536f8a 0000000000000001
[ 986.970333] 0000000000000000 ffff8802410e1ca8 ffffffff9115febc ffffffff91183ef7
[ 986.973173] ffff8801b478ef60 0000000000000000 ffff8802410e1ce8 ffff8801b3f07978
[ 986.975749] Call Trace:
[ 986.976700] dump_stack (lib/dump_stack.c:52)
[ 986.978875] warn_slowpath_common (kernel/panic.c:430)
[ 986.981924] ? process_one_work (kernel/workqueue.c:2224)
[ 986.984245] warn_slowpath_null (kernel/panic.c:465)
[ 986.986670] __blk_mq_run_hw_queue (arch/x86/include/asm/bitops.h:311 (discriminator 65) block/blk-mq.c:587 (discriminator 65))
[ 986.989000] ? process_one_work (include/linux/workqueue.h:186 kernel/workqueue.c:611 kernel/workqueue.c:638 kernel/workqueue.c:2220)
[ 986.991584] ? get_parent_ip (kernel/sched/core.c:2485)
[ 986.994168] blk_mq_run_work_fn (block/blk-mq.c:777)
[ 986.996379] process_one_work (kernel/workqueue.c:2227 include/linux/jump_label.h:105 include/trace/events/workqueue.h:111 kernel/workqueue.c:2232)
[ 986.998641] ? process_one_work (include/linux/workqueue.h:186 kernel/workqueue.c:611 kernel/workqueue.c:638 kernel/workqueue.c:2220)
[ 987.001352] worker_thread (kernel/workqueue.c:2354)
[ 987.003676] ? rescuer_thread (kernel/workqueue.c:2303)
[ 987.006703] kthread (kernel/kthread.c:210)
[ 987.009161] ? kthread_create_on_node (kernel/kthread.c:176)
[ 987.012536] ret_from_fork (arch/x86/kernel/entry_64.S:553)
[ 987.015272] ? kthread_create_on_node (kernel/kthread.c:176)

Thanks,
Sasha