From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:36053) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UdIdf-0002IB-S4 for qemu-devel@nongnu.org; Fri, 17 May 2013 07:15:57 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UdIdd-0001kF-F7 for qemu-devel@nongnu.org; Fri, 17 May 2013 07:15:55 -0400 Received: from mail-qe0-f52.google.com ([209.85.128.52]:32974) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UdIdc-0001k8-Sq for qemu-devel@nongnu.org; Fri, 17 May 2013 07:15:53 -0400 Received: by mail-qe0-f52.google.com with SMTP id 1so2540084qec.25 for ; Fri, 17 May 2013 04:15:52 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <87obcaaq4b.fsf@blackfin.pond.sub.org> References: <1368780720-14852-1-git-send-email-stefanha@redhat.com> <87obcaaq4b.fsf@blackfin.pond.sub.org> Date: Fri, 17 May 2013 13:15:52 +0200 Message-ID: From: Stefan Hajnoczi Content-Type: text/plain; charset=ISO-8859-1 Subject: Re: [Qemu-devel] [PATCH] tests: set MALLOC_PERTURB_ to expose memory bugs List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Markus Armbruster Cc: Lucas Meneghel Rodrigues , qemu-devel , Stefan Hajnoczi On Fri, May 17, 2013 at 11:54 AM, 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)) Covered in the commit description: "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." I didn't want to clutter output with "MALLOC_PERTURB_=123" on every run. AFAIK we have no log where this can be silently stashed. I guess we could write it to a file and add that to .gitignore. Stefan