Bug 83772

Summary:	turn off core dumps from the regression tests, more thoroughly
Product:	dbus	Reporter:	Simon McVittie <smcv>
Component:	core	Assignee:	Simon McVittie <smcv>
Status:	RESOLVED FIXED	QA Contact:
Severity:	normal
Priority:	medium	CC:	alban.crequy, thiago, walters
Version:	unspecified	Keywords:	patch
Hardware:	Other
OS:	All
Whiteboard:	review?
i915 platform:		i915 features:
Attachments:	On Linux, call prctl to disable core dumps

Description Simon McVittie 2014-09-11 16:04:21 UTC

The regression tests include an activatable service that deliberately raises SIGSEGV or segfaults, to verify that "process was killed by a signal" is reported correctly. It tries to turn off core dumps with setrlimit(), since its "crashes" are not really a problem.

However, when Linux's /proc/sys/kernel/core_pattern is set to a pipe (e.g. "|/usr/lib/corekeeper/dump %d %u %p-%u-%g-%s-%t-%h-%E.core" for the corekeeper utility), the kernel ignores RLIMIT_CORE. This is deliberate, to be able to catch crashes during boot before a configurable rlimit has been applied (e.g. see <https://lkml.org/lkml/2011/8/24/136>), but is inconvenient here.

We can use the Linux-specific prctl() syscall to turn off core dumps more thoroughly.

Comment 1 Simon McVittie 2014-09-11 16:04:54 UTC

Created attachment 106143 [details] [review]
On Linux, call prctl to disable core dumps

Whenever I forget to turn off corekeeper, the regression tests
take ages to record all test-segfault's crashes.

Comment 2 Alban Crequy 2014-09-12 16:48:14 UTC

Comment on attachment 106143 [details] [review]
On Linux, call prctl to disable core dumps

Review of attachment 106143 [details] [review]:
-----------------------------------------------------------------

::: configure.ac
@@ +600,5 @@
>  
> +# For test-segfault.c
> +AC_CHECK_HEADERS_ONCE([sys/prctl.h])
> +AC_CHECK_FUNCS_ONCE([prctl raise])
> +

Do the _ONCE checks work with old versions of autoconf?

Comment 3 Simon McVittie 2014-09-12 16:55:30 UTC

(In reply to comment #2)
> Do the _ONCE checks work with old versions of autoconf?

Yes. They were new in 2.59c, back in 2006.

Comment 4 Simon McVittie 2014-09-12 16:56:21 UTC

(In reply to comment #3)
> Yes. They were new in 2.59c, back in 2006.

(And we require 2.63 already.)

Comment 5 Alban Crequy 2014-09-14 13:22:38 UTC

It looks good to me then.

Comment 6 Simon McVittie 2014-09-15 12:02:57 UTC

Fixed in git for 1.8.8, 1.9.0

Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.