Re: [Alsa-devel] Re: ALSA regression: oops on shutdown

[Takashi Iwai <tiwai@suse.de>]

At Mon, 24 Apr 2006 15:34:30 +0200,
I wrote:
> 
> At Mon, 24 Apr 2006 07:51:44 +0400,
> Alexey Dobriyan wrote:
> > 
> > On Mon, Apr 24, 2006 at 07:11:42AM +0400, Alexey Dobriyan wrote:
> > > On Sun, Apr 23, 2006 at 10:39:19PM -0400, Lee Revell wrote:
> > >
> > > Andrew asked about precise steps of reproduction:
> > >
> > > 	rmmod snd_pcm_oss
> > >
> > > which is part of Gentoo install scripts (/etc/init.d/alsasound:134-140, to
> > > be precise) (basically lsmod | grep snd | xargs rmmod).
> > >
> > > BUG: unable to handle kernel paging request at virtual address 6b6b6b6b
> > >  printing eip:
> > > c016c6a4
> > > *pde = 00000000
> > > Oops: 0000 [#1]
> > > PREEMPT
> > > Modules linked in: snd_pcm_oss snd_mixer_oss snd_intel8x0 snd_ac97_codec snd_ac97_bus snd_pcm snd_timer snd soundcore snd_page_alloc ehci_hcd uhci_hcd usbcore
> > > CPU:    0
> > > EIP:    0060:[<c016c6a4>]    Not tainted VLI
> > > EFLAGS: 00010286   (2.6.17-rc2-6b426e785cb81e53dc2fc4dcf997661472b470ef #1)
> > > EIP is at remove_proc_entry+0x2c/0x11c
> > > eax: 00000000   ebx: deb48b80   ecx: ffffffff   edx: de11ed24
> > > esi: de11ed24   edi: 6b6b6b6b   ebp: de4cb000   esp: de4cbf28
> > > ds: 007b   es: 007b   ss: 0068
> > > Process rmmod (pid: 7735, threadinfo=de4cb000 task=c1487a90)
> > > Stack: <0>de11ed24 6b6b6b6b deb48b80 de11ed24 bf8590cc df93603b de4f0e78 00000000
> > >        df965fc8 de4f0d84 df967e74 df966184 de4f0d88 df95292d df967f00 00000000
> > >        c0125f7a 00000000 5f646e73 5f6d6370 0073736f de85d4a4 b7f27000 c013789d
> > > Call Trace:
> > >  [<df93603b>] snd_info_unregister+0x2e/0x44 [snd]
> > >  [<df965fc8>] snd_pcm_oss_proc_done+0x19/0x30 [snd_pcm_oss]
> > >  [<df966184>] snd_pcm_oss_unregister_minor+0x3b/0x3f [snd_pcm_oss]
> > >  [<df95292d>] snd_pcm_notify+0x4a/0x91 [snd_pcm]
> > >  [<c0125f7a>] sys_delete_module+0x113/0x138
> > >  [<c013789d>] do_munmap+0xe2/0xef
> > >  [<c010259b>] syscall_call+0x7/0xb
> > > Code: 85 d2 56 53 51 51 89 14 24 89 44 24 04 75 13 8d 4c 24 04 89 e2 e8 dd f7 ff ff 85 c0 0f 85 f2 00 00 00 8b 7c 24 04 31 c0 83 c9 ff <f2> ae f7 d1 49 b0 01 89 ce e8 fa 13 fa ff 8b 04 24 8d 58 38 83
> > > EIP: [<c016c6a4>] remove_proc_entry+0x2c/0x11c SS:ESP 0068:de4cbf28
> > >  BUG: rmmod/7735, lock held at task exit time!
> > >  [df960920] {register_mutex}
> > > .. held by:             rmmod: 7735 [c1487a90, 118]
> > > ... acquired at:               snd_pcm_notify+0x10/0x91 [snd_pcm]
> > 
> > Other symptoms are 6 (six) "prealloc" files, 3 "oss" files and 1 "oss"
> > directory (according to highlighting):
> > 
> > $ ls /proc/asound/
> > card0  devices  modules  oss  oss  prealloc  prealloc  prealloc  timers
> > 			      ^^^
> > 			      directory
> > 
> > cards  ICH5     oss      oss  pcm  prealloc  prealloc  prealloc  version
> > 
> > "ls -l" thinks all 4 "oss" files are files (again, according to
> > highlighting).
> 
> That's odd.  It implies that the proc file paths are flatten.

But, not all entries seem flatten (e.g. pcm0p, sub0, etc).
Could you show the output of "tree /proc/asound" ?


Takashi