Linus,
Please pull the latest perf-urgent-for-linus git tree from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git
perf-urgent-for-linus
# HEAD: 64aee2a965cf2954a038b5522f11d2cd2f0f8f3e perf/core: Fix group
{cpu,task} validation
A single fix to not allow nonsensical event groups that result in kernel
warnings.
Thanks,
Ingo
------------------>
Mark Rutland (1):
perf/core: Fix group {cpu,task} validation
kernel/events/core.c | 39 +++++++++++++++++++--------------------
1 file changed, 19 insertions(+), 20 deletions(-)
diff --git a/kernel/events/core.c b/kernel/events/core.c
index ee20d4c546b5..3504125871d2 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -10032,28 +10032,27 @@ SYSCALL_DEFINE5(perf_event_open,
goto err_context;
/*
- * Do not allow to attach to a group in a different
- * task or CPU context:
+ * Make sure we're both events for the same CPU;
+ * grouping events for different CPUs is broken; since
+ * you can never concurrently schedule them anyhow.
*/
- if (move_group) {
- /*
- * Make sure we're both on the same task, or both
- * per-cpu events.
- */
- if (group_leader->ctx->task != ctx->task)
- goto err_context;
+ if (group_leader->cpu != event->cpu)
+ goto err_context;
- /*
- * Make sure we're both events for the same CPU;
- * grouping events for different CPUs is broken; since
- * you can never concurrently schedule them anyhow.
- */
- if (group_leader->cpu != event->cpu)
- goto err_context;
- } else {
- if (group_leader->ctx != ctx)
- goto err_context;
- }
+ /*
+ * Make sure we're both on the same task, or both
+ * per-CPU events.
+ */
+ if (group_leader->ctx->task != ctx->task)
+ goto err_context;
+
+ /*
+ * Do not allow to attach to a group in a different task
+ * or CPU context. If we're moving SW events, we'll fix
+ * this up later, so allow that.
+ */
+ if (!move_group && group_leader->ctx != ctx)
+ goto err_context;
/*
* Only a group leader can be exclusive or pinned
