Thank you Michal, this is good news for me. I'll wait for this patch.
Regards, -- Carlos Rodrigues Engenheiro de Software Sénior Eurotux Informática, S.A. | www.eurotux.com (t) +351 253 680 300 (m) +351 911 926 110 On Qua, 2014-03-19 at 18:27 +0100, Michal Privoznik wrote: > On 19.03.2014 12:10, Carlos Rodrigues wrote: > > Hello Michal, > > > > I am using libvirt 1.1.3 and perl-Sys-Virt 1.1.3 and perl-5.16 on Fedora > > 19 x86_64 > > > > The zombie process appears after open libvirt connection with qemu-tls, > > and perl module is binding for libvirt library XS. > > > > Here is my running example with zombie process: > > > > $ perl test-chldhandle-bug-fixed.pl & sleep 15 && echo && ps axf | grep > > perl && echo > > [2] 12427 > > init... pid=12427 > > while... > > fork 1 > > end... pid=12430 > > receive chld > > fork 2 > > end... pid=12431 > > receive chld > > 2014-03-19 11:06:38.712+0000: 12427: info : libvirt version: 1.1.3.1, > > package: 2.fc19 (Unknown, 2014-03-17-15:02:00, cmar-laptop.lan) > > 2014-03-19 11:06:38.712+0000: 12427: warning : > > virNetTLSContextCheckCertificate:1140 : Certificate check failed > > Certificate [session] owner does not match the hostname 10.10.4.249 > > connection open > > fork 3 > > end... pid=12432 > > fork 4 > > end... pid=12440 > > > > 12427 pts/2 S 0:00 | \_ perl test-chldhandle-bug-fixed.pl > > 12432 pts/2 Z 0:00 | | \_ [perl] <defunct> > > 12440 pts/2 Z 0:00 | | \_ [perl] <defunct> > > 12442 pts/2 S+ 0:00 | \_ grep --color=auto perl > > Aha! It seems like this is only present if using tls, I was unable to > reproduce this with tcp or unix sockets. And when using tcp I can see > SIGCHLD being delivered while with tls it is not. That makes me wonder > if either libvirt or gnutls silently sets signal mask and not restore it > back. Because if I take a look at signal mask I can clearly see SIGCHLD > to be blocked (from /proc/$pid/status): > > SigPnd: 0000000000000000 > ShdPnd: 0000000000010000 > SigBlk: 0000000008011000 > SigIgn: 0000000000001080 > SigCgt: 0000000180010000 > > What we can see here is, SigBlk (the bitmask of blocked signals) > contains 0x801100 which is SIGPIPE, SIGCHLD and SIGWINCH. Right, why > would libvirt care about SIGWINCH anyway? Git greping it leads us to > virNetClientSetTLSSession(). I can clearly see there we are adding just > those three signals to a mask. Then setting this mask just prior to > calling poll() and then restoring back. Oh wait, we are not! > pthread_sigmask(SIG_BLOCK,...) is just adding new signals to the mask, > not overwriting the old one. So yes, this is clearly libvirt bug. > > If I use SIG_SETMASK there, I am no longer getting any zombies. I'll > post the patch shortly. > > Michal -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
