From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:46340) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UdHZp-00037u-RA for qemu-devel@nongnu.org; Fri, 17 May 2013 06:08:09 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UdHZg-0004L9-UU for qemu-devel@nongnu.org; Fri, 17 May 2013 06:07:53 -0400 Received: from mx1.redhat.com ([209.132.183.28]:45488) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UdHZg-0004Kb-MK for qemu-devel@nongnu.org; Fri, 17 May 2013 06:07:44 -0400 Received: from int-mx02.intmail.prod.int.phx2.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r4HA7h9p022737 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Fri, 17 May 2013 06:07:43 -0400 Date: Fri, 17 May 2013 11:07:38 +0100 From: "Daniel P. Berrange" Message-ID: <20130517100738.GF2342@redhat.com> References: <1368780720-14852-1-git-send-email-stefanha@redhat.com> <87obcaaq4b.fsf@blackfin.pond.sub.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <87obcaaq4b.fsf@blackfin.pond.sub.org> Subject: Re: [Qemu-devel] [PATCH] tests: set MALLOC_PERTURB_ to expose memory bugs Reply-To: "Daniel P. Berrange" List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Markus Armbruster Cc: Lucas Meneghel Rodrigues , qemu-devel@nongnu.org, Stefan Hajnoczi On Fri, May 17, 2013 at 11:54:12AM +0200, Markus Armbruster wrote: > Stefan Hajnoczi writes: > > > glibc wipes malloc(3) memory when the MALLOC_PERTURB_ environment > > variable is set. The value of the environment variable determines the > > bit pattern used to wipe memory. For more information, see > > http://udrepper.livejournal.com/11429.html. > > > > Set MALLOC_PERTURB_ for gtester and qemu-iotests. Note we always set > > the environment variable to 1 so the test is deterministic. Setting a > > random variable might expose more bugs but would be harder to reproduce. > > > > Both make check and qemu-iotests pass with MALLOC_PERTURB_ enabled. > > > > Signed-off-by: Stefan Hajnoczi > > --- > > Lucas noticed KVM autotest failures when enabling MALLOC_PERTURB_. By enabling > > it for in-tree test suites we can detect memory management errors earlier. > > > > tests/Makefile | 4 +++- > > tests/qemu-iotests/check | 2 +- > > 2 files changed, 4 insertions(+), 2 deletions(-) > > > > diff --git a/tests/Makefile b/tests/Makefile > > index a307d5a..25f6d28 100644 > > --- a/tests/Makefile > > +++ b/tests/Makefile > > @@ -171,6 +171,7 @@ GCOV_OPTIONS = -n $(if $(V),-f,) > > $(patsubst %, check-qtest-%, $(QTEST_TARGETS)): check-qtest-%: $(check-qtest-y) > > $(if $(CONFIG_GCOV),@rm -f *.gcda */*.gcda */*/*.gcda */*/*/*.gcda,) > > $(call quiet-command,QTEST_QEMU_BINARY=$*-softmmu/qemu-system-$* \ > > + MALLOC_PERTURB_=1 \ > > gtester $(GTESTER_OPTIONS) -m=$(SPEED) $(check-qtest-$*-y),"GTESTER $@") > > $(if $(CONFIG_GCOV),@for f in $(gcov-files-$*-y); do \ > > echo Gcov report for $$f:;\ > > If you want punishment, why not go for extra punishment? > > MALLOC_PERTURB_=$(($RANDOM % 255 + 1)) That could lead to non-reproducable failures though. I think it is better to use a fixed value so that you're more likely to be able to reproduce the issue every time you run the tests. Rather than setting MALLOC_PERTURB_=1 unconditionally in the Makefile though, it ought to honour any existing MALLOC_PERTURB_ env variable the user has set. That could let automated test harness run repeatedly with random MALLOC_PERTURB_, while still giving a deterministic value for developers by default. Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|