From 978520b75f0a1ce82b17e1e8186417250de6d545 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Fri, 12 Oct 2012 15:12:55 +0200 Subject: ALSA: usb-audio: Fix races at disconnection Close some races at disconnection of a USB audio device by adding the chip->shutdown_mutex and chip->shutdown check at appropriate places. The spots to put bandaids are: - PCM prepare, hw_params and hw_free - where the usb device is accessed for communication or get speed, in mixer.c and others; the device speed is now cached in subs->speed instead of accessing to chip->dev The accesses in PCM open and close don't need the mutex protection because these are already handled in the core PCM disconnection code. The autosuspend/autoresume codes are still uncovered by this patch because of possible mutex deadlocks. They'll be covered by the upcoming change to rwsem. Also the mixer codes are untouched, too. These will be fixed in another patch, too. Reported-by: Matthieu CASTET Cc: Signed-off-by: Takashi Iwai --- sound/usb/proc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'sound/usb/proc.c') diff --git a/sound/usb/proc.c b/sound/usb/proc.c index ebc1a5b5b3f1..d218f763501f 100644 --- a/sound/usb/proc.c +++ b/sound/usb/proc.c @@ -108,7 +108,7 @@ static void proc_dump_substream_formats(struct snd_usb_substream *subs, struct s } snd_iprintf(buffer, "\n"); } - if (snd_usb_get_speed(subs->dev) != USB_SPEED_FULL) + if (subs->speed != USB_SPEED_FULL) snd_iprintf(buffer, " Data packet interval: %d us\n", 125 * (1 << fp->datainterval)); // snd_iprintf(buffer, " Max Packet Size = %d\n", fp->maxpacksize); @@ -124,7 +124,7 @@ static void proc_dump_ep_status(struct snd_usb_substream *subs, return; snd_iprintf(buffer, " Packet Size = %d\n", ep->curpacksize); snd_iprintf(buffer, " Momentary freq = %u Hz (%#x.%04x)\n", - snd_usb_get_speed(subs->dev) == USB_SPEED_FULL + subs->speed == USB_SPEED_FULL ? get_full_speed_hz(ep->freqm) : get_high_speed_hz(ep->freqm), ep->freqm >> 16, ep->freqm & 0xffff); -- cgit v1.2.3