From 3b20b9b4e985fcc48b4eea401cb289a856422c93 Mon Sep 17 00:00:00 2001 From: Muli Ben-Yehuda Date: Tue, 17 Jul 2007 04:05:15 -0700 Subject: OSS trident: fix locking around write_voice_regs trident_write_voice_regs() was getting called with the card spinlock held in only some cases. Fix it. Explanation: we allocate a new virtual channel in open, and then we frob some hardware registers (in write_voice_regs) for that channel. But the hardware registers are shared with other channels, which may be trying to frob the some registers (albeit for another channel) via ioctl(SNDCTL_DSP_SPEED). Fixed bugzilla.kernel.org bug #8172 (http://bugme.osdl.org/show_bug.cgi?id=8172) Signed-off-by: Muli Ben-Yehuda Cc: Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- sound/oss/trident.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'sound/oss') diff --git a/sound/oss/trident.c b/sound/oss/trident.c index 3e408f491927..2e3e78e1bf67 100644 --- a/sound/oss/trident.c +++ b/sound/oss/trident.c @@ -2702,6 +2702,7 @@ trident_open(struct inode *inode, struct file *file) struct trident_card *card = devs; struct trident_state *state = NULL; struct dmabuf *dmabuf = NULL; + unsigned long flags; /* Added by Matt Wu 01-05-2001 */ /* TODO: there's some redundacy here wrt the check below */ @@ -2779,7 +2780,9 @@ trident_open(struct inode *inode, struct file *file) /* set default channel attribute to normal playback */ dmabuf->channel->attribute = CHANNEL_PB; } + spin_lock_irqsave(&card->lock, flags); trident_set_dac_rate(state, 8000); + spin_unlock_irqrestore(&card->lock, flags); } if (file->f_mode & FMODE_READ) { @@ -2797,7 +2800,9 @@ trident_open(struct inode *inode, struct file *file) dmabuf->channel->attribute = (CHANNEL_REC | PCM_LR | MONO_MIX); } + spin_lock_irqsave(&card->lock, flags); trident_set_adc_rate(state, 8000); + spin_unlock_irqrestore(&card->lock, flags); /* Added by Matt Wu 01-05-2001 */ if (card->pci_id == PCI_DEVICE_ID_ALI_5451) -- cgit v1.2.1