From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paul_Woegerer@mentor.com (Woegerer, Paul) Date: Fri, 28 Feb 2014 13:38:55 +0100 Subject: [lttng-dev] baddr feature triggers deadlock in lttng-ust In-Reply-To: <561294755.31915.1393536606539.JavaMail.zimbra@efficios.com> References: <561294755.31915.1393536606539.JavaMail.zimbra@efficios.com> Message-ID: <5310835F.10909@mentor.com> I have looked a bit into the issue... The ust_locking inside the dl_iterate_phdr triggers the deadlock. If I just collect the base address info inside dl_iterate_phdr and dump the collected data with trace_baddr afterwards (outside the dl_iterate_phdr iteration) the deadlock will be prevented. I'm now going to create a patch that implements this approach. Thanks, Paul On 02/27/2014 10:30 PM, Mathieu Desnoyers wrote: > Hi Paul, > > Please see http://bugs.lttng.org/issues/745, which explains a deadlock > we just found out. > > We might have to disable the baddr dump feature, since our release is > tomorrow. We'll have to re-think our locking to protect operations > using the dynamic loader lock against fork, clone, and daemon. > > Thanks, > > Mathieu > -- Paul Woegerer, SW Development Engineer Sourcery Analyzer Mentor Graphics, Embedded Software Division