[pulseaudio-discuss] PA 7.0 crash with KDE

[Takashi Iwai]

On Fri, 16 Oct 2015 09:16:04 +0200,
David Henningsson wrote:
> 
> (Adding pulseaudio-discuss to CC)
> 
> On 2015-10-15 16:26, Takashi Iwai wrote:
> > Hi David,
> >
> > we got bug reports with PA 7.0 where the recent KDE crashes.
> > It seems that srbchannel=no works around it, so there is still
> > something fishy there.
> >
> > The bug report is found at
> >    http://bugzilla.opensuse.org/show_bug.cgi?id=950487
> 
> Hi Takashi and thanks for reporting.
> 
> I've tried running PA 7.0's pactl under valgrind, and it reports no 
> errors here. Still, looking at the one of the backtraces the value of f 
> is something interesting:
> 
> #6  flush (f=f at entry=0x4545454545454545) at pulsecore/fdsem.c:143
> #7  0x00007fe30f378fc2 in pa_fdsem_before_poll (f=0x4545454545454545) at 
> pulsecore/fdsem.c:295
> #8  0x00007fe30f38f697 in srbchannel_rwloop (sr=0x25bdd40) at 
> pulsecore/srbchannel.c:203
> 
> Does 0x4545454545454545 mean anything specific on OpenSUSE? (Like, a 
> magic clear value or something?)

I don't think it's openSUSE specific.  It's likely the guard put by
either gcc or glibc.
FWIW, we pass the default optimization flags like:
  CFLAGS=-fmessage-length=0 -grecord-gcc-switches -O2 -Wall \
    -D_FORTIFY_SOURCE=2 -fstack-protector -funwind-tables \
    -fasynchronous-unwind-tables -g -fPIE

The problem was reported from both gcc-4.8 and gcc-5.x systems, so the
gcc version is likely irrelevant.

> Also, are there any distro patches to OpenSUSE and if so, where can I 
> find them?

No, there is no patches apparently relevant with this.  Actually there are
three patches, one is to check an additional environment check in
start-pulseaudio-x11, another is to suppress an error log at
sockaddr_prepare(), and the last is a fix in memset() size in
echo-cancel/adrian-aec.c.  But all these should be safe.

All sources, patches, build log and binaries are found in OBS, e.g. at
  https://build.opensuse.org/package/show/multimedia:libs/pulseaudio


thanks,

Takashi