Messages in this thread | | | Date | Thu, 01 Jul 2010 10:09:03 +0900 | From | Masami Hiramatsu <> | Subject | Re: [Bugfix] unregister_trace_probe needs to be called under mutex |
| |
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 > > Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Ah, right! That's definately needed.
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Thank you!
> --- > > 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; > } >
| |