kern/51965: audio open panics LOCKDEBUG kernel

[mlelstv%serpens.de@localhost]

>Number:         51965
>Category:       kern
>Synopsis:       audio open panics LOCKDEBUG kernel
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Feb 12 14:10:01 +0000 2017
>Originator:     Michael van Elst
>Release:        NetBSD 7.99.59
>Organization:
	
>Environment:
	
	
System: NetBSD tazz 7.99.59 NetBSD 7.99.59 (TAZZ) #5: Sat Feb 11 21:09:06 CET 2017 mlelstv@gossam:/home/netbsd-current/obj.amd64/home/netbsd-current/src/sys/arch/amd64/compile/TAZZ amd64
Architecture: x86_64
Machine: amd64
>Description:
opening /dev/audio on a LOCKDEBUG kernel causes an immediate assert_sleepable
panic.

audioopen() calls audio_open().

audio_open() calls grow_mixer_states() while holding sc->sc_intr_lock.

grow_mixer_states() tries to kmem_zalloc(..., KM_SLEEP) which triggers
the assertion.

You must not sleep while holding a spin mutex.

>How-To-Repeat:
Run something that opens /dev/audio under LOCKDEBUG.

>Fix:
	

>Unformatted: