At Thu, 5 Apr 2007 15:53:50 +0200, Frederik Deweerdt wrote: > > On Mon, Apr 02, 2007 at 10:47:45PM -0700, Andrew Morton wrote: > > > > ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.21-rc5/2.6.21-rc5-mm4/ > > > Hi, > > When launching "jackd -d alsa", lockdep issues the following warning: > [39701.405086] ============================================= > [39701.405093] [ INFO: possible recursive locking detected ] > [39701.405107] 2.6.21-rc5-mm4 #2 > [39701.405109] --------------------------------------------- > [39701.405112] jackd/17366 is trying to acquire lock: > [39701.405114] (&substream->self_group.lock){....}, at: [<c034d3c0>] > snd_pcm_action_group+0x90/0x240 > [39701.405131] > [39701.405131] but task is already holding lock: > [39701.405134] (&substream->self_group.lock){....}, at: [<c034d63f>] > snd_pcm_action_lock_irq+0x3f/0xb0 > [39701.405141] > [39701.405142] other info that might help us debug this: > [39701.405145] 3 locks held by jackd/17366: > [39701.405147] #0: (snd_pcm_link_rwlock){....}, at: [<c034d627>] > snd_pcm_action_lock_irq+0x27/0xb0 > [39701.405155] #1: (&substream->group->lock){....}, at: [<c034d638>] > snd_pcm_action_lock_irq+0x38/0xb0 > [39701.405163] #2: (&substream->self_group.lock){....}, at: [<c034d63f>] > snd_pcm_action_lock_irq+0x3f/0xb0 > [39701.405171] > [39701.405171] stack backtrace: > [39701.405174] [<c0103b8a>] show_trace_log_lvl+0x1a/0x30 > [39701.405179] [<c0104912>] show_trace+0x12/0x20 > [39701.405183] [<c01049c6>] dump_stack+0x16/0x20 > [39701.405187] [<c013b980>] __lock_acquire+0xbd0/0x1040 > [39701.405193] [<c013be60>] lock_acquire+0x70/0x90 > [39701.405197] [<c0407846>] _spin_lock+0x36/0x50 > [39701.405203] [<c034d3c0>] snd_pcm_action_group+0x90/0x240 > [39701.405207] [<c034d653>] snd_pcm_action_lock_irq+0x53/0xb0 > [39701.405211] [<c035046f>] snd_pcm_common_ioctl1+0x35f/0xfb0 > [39701.405215] [<c0351544>] snd_pcm_playback_ioctl1+0x34/0x420 > [39701.405219] [<c03519f3>] snd_pcm_playback_ioctl+0x43/0x50 > [39701.405223] [<c017ecc8>] do_ioctl+0x28/0x80 > [39701.405229] [<c017ed77>] vfs_ioctl+0x57/0x290 > [39701.405233] [<c017efe9>] sys_ioctl+0x39/0x60 > [39701.405237] [<c0102bf4>] sysenter_past_esp+0x5d/0x99 > [39701.405240] ======================= > > The attached lockdep annotation silences the warning. > Regards, > Frederik > > Signed-off-by: Frederik Deweerdt <[EMAIL PROTECTED]>
Thanks, applied to ALSA tree now. (I did a similar fix ago but forgot to merge to the upstream...) Takashi > > --- 2.6.21-rc5-mm3/sound/core/pcm_native.c 2007-03-30 21:41:18.000000000 > +0200 > +++ 2.6.21-rc5-mm4/sound/core/pcm_native.c 2007-04-05 15:01:19.000000000 > +0200 > @@ -718,7 +718,8 @@ static int snd_pcm_action_group(struct a > > snd_pcm_group_for_each_entry(s, substream) { > if (do_lock && s != substream) > - spin_lock(&s->self_group.lock); > + spin_lock_nested(&s->self_group.lock, > + SINGLE_DEPTH_NESTING); > res = ops->pre_action(s, state); > if (res < 0) > goto _unlock; > - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/