[PATCH 05/20] powerpc/perf: Reject EBB events which specify a sample_type

Michael Ellerman mpe at ellerman.id.au
Fri Mar 14 16:00:30 EST 2014


Although we already block EBB events which request sampling using
sample_period, technically it's possible for an event to set sample_type
but not sample_period.

Nothing terrible will happen if an EBB event does specify sample_type,
but it signals a major confusion on the part of userspace, and so we do
them the favor of rejecting it.

Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
---
 arch/powerpc/perf/core-book3s.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c
index 53ac1b2..1e095fd 100644
--- a/arch/powerpc/perf/core-book3s.c
+++ b/arch/powerpc/perf/core-book3s.c
@@ -503,8 +503,11 @@ static int ebb_event_check(struct perf_event *event)
 		if (!leader->attr.pinned || !leader->attr.exclusive)
 			return -EINVAL;
 
-		if (event->attr.inherit || event->attr.sample_period ||
-		    event->attr.enable_on_exec || event->attr.freq)
+		if (event->attr.freq ||
+		    event->attr.inherit ||
+		    event->attr.sample_type ||
+		    event->attr.sample_period ||
+		    event->attr.enable_on_exec)
 			return -EINVAL;
 	}
 
-- 
1.8.3.2



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