Messages in this thread | | | Subject | Re: [Bugfix] unregister_trace_probe needs to be called under mutex | From | Steven Rostedt <> | Date | Wed, 30 Jun 2010 12:00:29 -0400 |
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On Wed, 2010-06-30 at 11:44 +0200, Peter Zijlstra wrote: > On Wed, 2010-06-30 at 14:15 +0530, Srikar Dronamraju wrote: > > Comment in unregister_trace_probe() says probe_lock will be held > > when it gets called. However there is a case where it might called > > without the probe_lock being held. Also since we are traversing the > > probe_list and deleting an element from the probe_list, probe_lock > > should be held. > > > > This was first pointed in uprobes traceevent review by Frederic > > Weisbecker here. (http://lkml.org/lkml/2010/5/12/106) > > > > This patch is needed for both 2.6.35-rc3 and 2.6.35-rc3-tip
Acked-by: Steven Rostedt <rostedt@goodmis.org>
> > > > Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> > > --- > > > > diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c > > index 4f11a56..67670cd 100644 > > --- a/kernel/trace/trace_kprobe.c > > +++ b/kernel/trace/trace_kprobe.c > > @@ -269,14 +269,17 @@ static int create_trace_probe(int argc, char **argv) > > pr_info("Delete command needs an event name.\n"); > > return -EINVAL; > > } > > + mutex_lock(&probe_lock); > > tp = find_probe_event(event, group); > > if (!tp) { > > + mutex_unlock(&probe_lock); > > pr_info("Event %s/%s doesn't exist.\n", group, event); > > return -ENOENT; > > } > > /* delete an event */ > > unregister_trace_probe(tp); > > free_trace_probe(tp); > > + mutex_unlock(&probe_lock); > > return 0; > > } > > Shouldn't all that go through steven's ->reg() interface?
Nah, this is specific to the kprobe code. Has really nothing to do with the ->reg() interface.
-- Steve
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