Re: Building packages with buildd and qemu-kvm

[Svante Signell]

On Wed, 2011-04-13 at 11:10 +0200, Samuel Thibault wrote:
> Svante Signell, le Wed 13 Apr 2011 11:05:30 +0200, a écrit :
> > On Wed, 2011-04-13 at 10:43 +0200, Samuel Thibault wrote:
> > > Svante Signell, le Wed 13 Apr 2011 07:46:54 +0200, a écrit :
> > > > make[1]: *** [lapack_testing] Error 141
> > > > 
> > > > Both tests end with a signal being sent for a kill from fakeroot in the
> > > > first case and in libfakreoot during a read operation. Both had happen
> > > > during redirection of stdin and stdout. Why issuing a kill in the
> > > > middle of execution? Are these functions also handled by libpipe? If
> > > 
> > > 141 is 128 + 13, i.e. SIGPIPE. This is supposed to happen when the
> > > reader part of a pipe has disappeared while the writer was trying to
> > > write to the pipe. It's not supposed to happen on the reader part.
> > 
> > How to interpret your answer, is there a problem with libpipe or not?
> 
> Err, yes. "It's not supposed to happen" => there's a bug. Since it's on
> a pipe, it's most probably on pflocal or libpipe. glibc could be at
> stake, but I doubt it, since it doesn't do anything different for files
> or for pipes.

How to best debug libpipe, setting breakpoints in Ggdb?

> > BTW: The kill command comes from a timer called from in debian/rules. I
> > tried to increase TIMEOUT from 1800 to 3600, but the build seems to bail
> > out at the same place for me. Trying again with TIMEOUT:=4800 now.
> 
> Ah! then it's most probably a way simpler, different story: the reader
> probably just got hung, and debian/rules simply killed it out of
> patience, which thus made the writer get SIGPIPE, which is normal. So
> the real bug is actually happening simply in the atlas process at the
> read end. 

Now the build stop at another place (looks like random places). It is
definitely not the timer causing this.

libfakeroot: read: Connection reset by peer
make[1]: *** [lapack_testing] Error 141
make[1]: Leaving directory `/home/srs/DEBs/lapack/lapack-3.3.0'
make: *** [testing/xeigtsts] Error 2
/usr/bin/fakeroot: line 1: kill: (21461) - No such process
dpkg-buildpackage: error: fakeroot debian/rules binary gave error exit
status 2

> When you see no progress from the build, check out the last
> started process and what they are doing.

I get output all the time until the crash. There is no process left to
monitor. After error 141 no build-related process is executing.