Bug 81161

[   13.305589] =============================================
[   13.305590] [ INFO: possible recursive locking detected ]
[   13.305591] 3.15.7-200.fc20.x86_64+debug #1 Not tainted
[   13.305592] ---------------------------------------------
[   13.305593] pulseaudio/1230 is trying to acquire lock:
[   13.305593]  (&(&substream->self_group.lock)->rlock/1){......}, at: [<ffffffffa02fa483>] snd_pcm_action_group+0xa3/0x240 [snd_pcm]
[   13.305601] 
but task is already holding lock:
[   13.305602]  (&(&substream->self_group.lock)->rlock/1){......}, at: [<ffffffffa02fa483>] snd_pcm_action_group+0xa3/0x240 [snd_pcm]
[   13.305607] 
other info that might help us debug this:
[   13.305607]  Possible unsafe locking scenario:

[   13.305608]        CPU0
[   13.305609]        ----
[   13.305609]   lock(&(&substream->self_group.lock)->rlock/1);
[   13.305611]   lock(&(&substream->self_group.lock)->rlock/1);
[   13.305612] 
 *** DEADLOCK ***

[   13.305613]  May be due to missing lock nesting notation

[   13.305615] 4 locks held by pulseaudio/1230:
[   13.305615]  #0:  (snd_pcm_link_rwlock){......}, at: [<ffffffffa02fbff7>] snd_pcm_drop+0x57/0xe0 [snd_pcm]
[   13.305620]  #1:  (&(&substream->self_group.lock)->rlock){......}, at: [<ffffffffa02fbfff>] snd_pcm_drop+0x5f/0xe0 [snd_pcm]
[   13.305624]  #2:  (&(&substream->group->lock)->rlock){......}, at: [<ffffffffa02fbe21>] snd_pcm_action+0x31/0xa0 [snd_pcm]
[   13.305628]  #3:  (&(&substream->self_group.lock)->rlock/1){......}, at: [<ffffffffa02fa483>] snd_pcm_action_group+0xa3/0x240 [snd_pcm]
[   13.305632] 
stack backtrace:
[   13.305634] CPU: 2 PID: 1230 Comm: pulseaudio Not tainted 3.15.7-200.fc20.x86_64+debug #1
[   13.305635] Hardware name: Gigabyte Technology Co., Ltd. Z87M-D3H/Z87M-D3H, BIOS 11b 06/12/2014
[   13.305636]  0000000000000000 000000001e51d61a ffff8807eb0bfbb8 ffffffff817da3c6
[   13.305638]  ffffffff82561be0 ffff8807eb0bfc88 ffffffff810fc0c0 ffffffff81023505
[   13.305640]  ffff8807eb0bfbe8 ffffffff81023505 000000000000059b 0000000000000000
[   13.305642] Call Trace:
[   13.305646]  [<ffffffff817da3c6>] dump_stack+0x4d/0x66
[   13.305649]  [<ffffffff810fc0c0>] __lock_acquire+0x1700/0x1c90
[   13.305653]  [<ffffffff81023505>] ? native_sched_clock+0x35/0xa0
[   13.305654]  [<ffffffff81023505>] ? native_sched_clock+0x35/0xa0
[   13.305656]  [<ffffffff810facca>] ? __lock_acquire+0x30a/0x1c90
[   13.305658]  [<ffffffff810fce29>] lock_acquire+0x99/0x1d0
[   13.305661]  [<ffffffffa02fa483>] ? snd_pcm_action_group+0xa3/0x240 [snd_pcm]
[   13.305663]  [<ffffffff817e353c>] _raw_spin_lock_nested+0x3c/0x80
[   13.305666]  [<ffffffffa02fa483>] ? snd_pcm_action_group+0xa3/0x240 [snd_pcm]
[   13.305670]  [<ffffffffa02fa483>] snd_pcm_action_group+0xa3/0x240 [snd_pcm]
[   13.305684]  [<ffffffffa02fbe54>] snd_pcm_action+0x64/0xa0 [snd_pcm]
[   13.305687]  [<ffffffffa02fc020>] snd_pcm_drop+0x80/0xe0 [snd_pcm]
[   13.305690]  [<ffffffffa02fdfd0>] snd_pcm_common_ioctl1+0x8f0/0xc40 [snd_pcm]
[   13.305693]  [<ffffffff8135513d>] ? avc_has_perm+0x16d/0x360
[   13.305705]  [<ffffffff81355004>] ? avc_has_perm+0x34/0x360
[   13.305709]  [<ffffffffa02fe4db>] snd_pcm_playback_ioctl1+0x1bb/0x2e0 [snd_pcm]
[   13.305712]  [<ffffffffa02fe630>] snd_pcm_playback_ioctl+0x30/0x40 [snd_pcm]
[   13.305715]  [<ffffffff81249d80>] do_vfs_ioctl+0x300/0x520
[   13.305717]  [<ffffffff81255e15>] ? __fget+0x5/0x300
[   13.305719]  [<ffffffff8124a021>] SyS_ioctl+0x81/0xa0
[   13.305721]  [<ffffffff8115673c>] ? __audit_syscall_entry+0x9c/0xf0
[   13.305723]  [<ffffffff817ee2e9>] system_call_fastpath+0x16/0x1b
[   13.930141] ata2.00: configured for UDMA/133
[   13.930147] ata2: EH complete
[   13.930966] ata1.00: configured for UDMA/133
[   13.930969] ata1: EH complete

Created attachment 144761 [details]
kernel log

The kernel warning is harmless, known to be false positive.
Nevertheless, it's been already fixed in the recent upstream kernels.

Feel free to reopen if you still see the issue with the latest kernel.  Thanks.