From: Takashi Iwai <tiwai@suse.de>
Date: Mon, 13 Oct 2014 21:18:02 +0000 (+0200)
Subject: ALSA: emu10k1: Fix deadlock in synth voice lookup
X-Git-Tag: fixes-against-v3.18-rc2~34^2~1
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=95926035b187cc9fee6fb61385b7da9c28123f74;p=pandora-kernel.git

ALSA: emu10k1: Fix deadlock in synth voice lookup

The emu10k1 voice allocator takes voice_lock spinlock.  When there is
no empty stream available, it tries to release a voice used by synth,
and calls get_synth_voice.  The callback function,
snd_emu10k1_synth_get_voice(), however, also takes the voice_lock,
thus it deadlocks.

The fix is simply removing the voice_lock holds in
snd_emu10k1_synth_get_voice(), as this is always called in the
spinlock context.

Reported-and-tested-by: Arthur Marsh <arthur.marsh@internode.on.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---

Reading git-diff-tree failed