From: Julia Lawall Date: Sat, 18 Jul 2009 15:26:14 +0000 (+0200) Subject: ALSA: sound/isa: convert nested spin_lock_irqsave to spin_lock X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=fcb2954b9621dfeaca92f6a11dac69cfdfaa6705;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git ALSA: sound/isa: convert nested spin_lock_irqsave to spin_lock If spin_lock_irqsave is called twice in a row with the same second argument, the interrupt state at the point of the second call overwrites the value saved by the first call. Indeed, the second call does not need to save the interrupt state, so it is changed to a simple spin_lock. The semantic match that finds this problem is as follows: (http://www.emn.fr/x-info/coccinelle/) // @@ expression lock1,lock2; expression flags; @@ *spin_lock_irqsave(lock1,flags) ... when != flags *spin_lock_irqsave(lock2,flags) // Signed-off-by: Julia Lawall Signed-off-by: Takashi Iwai --- diff --git a/sound/isa/gus/gus_pcm.c b/sound/isa/gus/gus_pcm.c index edb11eefdfe3..2dcf45bf7293 100644 --- a/sound/isa/gus/gus_pcm.c +++ b/sound/isa/gus/gus_pcm.c @@ -795,13 +795,13 @@ static int snd_gf1_pcm_volume_put(struct snd_kcontrol *kcontrol, struct snd_ctl_ if (!(pcmp->flags & SNDRV_GF1_PCM_PFLG_ACTIVE)) continue; /* load real volume - better precision */ - spin_lock_irqsave(&gus->reg_lock, flags); + spin_lock(&gus->reg_lock); snd_gf1_select_voice(gus, pvoice->number); snd_gf1_ctrl_stop(gus, SNDRV_GF1_VB_VOLUME_CONTROL); vol = pvoice == pcmp->pvoices[0] ? gus->gf1.pcm_volume_level_left : gus->gf1.pcm_volume_level_right; snd_gf1_write16(gus, SNDRV_GF1_VW_VOLUME, vol); pcmp->final_volume = 1; - spin_unlock_irqrestore(&gus->reg_lock, flags); + spin_unlock(&gus->reg_lock); } spin_unlock_irqrestore(&gus->voice_alloc, flags); return change;