Le mercredi 21 octobre 2009 22:33:56, vous avez écrit : > On Wed, Oct 21, 2009 at 07:11:40PM +0300, Remi Denis-Courmont wrote: > > Package: libc6-i686 > > Version: 2.10.1-1 > > Severity: critical > > Justification: breaks unrelated software > > > > > > Hello, > > > > With the upgrade to 2.10.1, pthread_cond_wait() fails to re-acquire the > > provided mutex when acting on a deferred cancellation event from > > another thread. This is seen if (and apparently, only if) another thread > > acquires the same mutex after cancellation is initiated, but before the > > cancelled thread executes cancellation cleanup handlers. > > > > I could not reproduce the problem with plain libc6. It only occurs with > > libc6-i686 installed. > > > > I wrote a simple test case at: > > http://www.remlab.net/files/divers/condfail.c > > This test shows the same behaviour on both lenny and sid version, that > is it prints "1" and "2", but never triggers an assertion. > > Are there other conditions for this test to fail?
I don't know. It reproduces pretty much 100% here: % ./a.out 1 2 a.out: test.c:18: cleanup_lock: Assertion `val == 0' failed. Abandon I'm running on a single core SMT (P4/HT namely), so instruction cycle timing might be very different from what an UP or non-SMT SMP gets :( In any case, the fact that is only occurs with libc6-i686 hints at incorrect use of atomic ops, I guess... -- Rémi Denis-Courmont http://www.remlab.net/ -- To UNSUBSCRIBE, email to debian-glibc-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
