[for-next][PATCH 06/16] ring-buffer: Clear pages on error in ring_buffer_subbuf_order_set() failure

From: Steven Rostedt
Date: Thu Dec 21 2023 - 11:11:19 EST


From: "Steven Rostedt (Google)" <rostedt@xxxxxxxxxxx>

On failure to allocate ring buffer pages, the pointer to the CPU buffer
pages is freed, but the pages that were allocated previously were not.
Make sure they are freed too.

Link: https://lore.kernel.org/linux-trace-kernel/20231219185629.179352802@xxxxxxxxxxx

Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Tzvetomir Stoyanov <tz.stoyanov@xxxxxxxxx>
Cc: Vincent Donnefort <vdonnefort@xxxxxxxxxx>
Cc: Kent Overstreet <kent.overstreet@xxxxxxxxx>
Fixes: f9b94daa542a ("tracing: Set new size of the ring buffer sub page")
Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
---
kernel/trace/ring_buffer.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index c2afcf98ea91..3c11e8e811ed 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -5927,6 +5927,7 @@ int ring_buffer_subbuf_order_set(struct trace_buffer *buffer, int order)
for_each_buffer_cpu(buffer, cpu) {
if (!cpu_buffers[cpu])
continue;
+ rb_free_cpu_buffer(cpu_buffers[cpu]);
kfree(cpu_buffers[cpu]);
}
kfree(cpu_buffers);
--
2.42.0