[PATCH 2/7] ring-buffer: check for failed allocation in ring buffer benchmark

[Steven Rostedt <rostedt@goodmis.org>]

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From: Steven Rostedt <srostedt@redhat.com>

The result of the allocation of the ring buffer read page in the
ring buffer bench mark does not check the return to see if a page
was actually allocated. This patch fixes that.

[ Impact: avoid NULL dereference ]

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 kernel/trace/ring_buffer_benchmark.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/kernel/trace/ring_buffer_benchmark.c b/kernel/trace/ring_buffer_benchmark.c
index 747244a..dcd75e9 100644
--- a/kernel/trace/ring_buffer_benchmark.c
+++ b/kernel/trace/ring_buffer_benchmark.c
@@ -84,6 +84,9 @@ static enum event_status read_page(int cpu)
 	int i;
 
 	bpage = ring_buffer_alloc_read_page(buffer);
+	if (!bpage)
+		return EVENT_DROPPED;
+
 	ret = ring_buffer_read_page(buffer, &bpage, PAGE_SIZE, cpu, 1);
 	if (ret >= 0) {
 		rpage = bpage;
-- 
1.6.2.4

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