6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Steven Rostedt <rostedt@xxxxxxxxxxx> [ Upstream commit 60b8f711143de7cd9c0f55be0fe7eb94b19eb5c7 ] Currently if __tracing_resize_ring_buffer() returns an error, the tracing_resize_ringbuffer() returns -ENOMEM. But it may not be a memory issue that caused the function to fail. If the ring buffer is memory mapped, then the resizing of the ring buffer will be disabled. But if the user tries to resize the buffer, it will get an -ENOMEM returned, which is confusing because there is plenty of memory. The actual error returned was -EBUSY, which would make much more sense to the user. Cc: stable@xxxxxxxxxxxxxxx Cc: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx> Cc: Vincent Donnefort <vdonnefort@xxxxxxxxxx> Link: https://lore.kernel.org/20250213134132.7e4505d7@xxxxxxxxxxxxxxxxxx Fixes: 117c39200d9d7 ("ring-buffer: Introducing ring-buffer mapping functions") Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx> Reviewed-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- kernel/trace/trace.c | 8 +------- 1 file changed, 1 insertion(+), 7 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index f03eef90de54c..1142a7802bb60 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -5998,8 +5998,6 @@ static int __tracing_resize_ring_buffer(struct trace_array *tr, ssize_t tracing_resize_ring_buffer(struct trace_array *tr, unsigned long size, int cpu_id) { - int ret; - guard(mutex)(&trace_types_lock); if (cpu_id != RING_BUFFER_ALL_CPUS) { @@ -6008,11 +6006,7 @@ ssize_t tracing_resize_ring_buffer(struct trace_array *tr, return -EINVAL; } - ret = __tracing_resize_ring_buffer(tr, size, cpu_id); - if (ret < 0) - ret = -ENOMEM; - - return ret; + return __tracing_resize_ring_buffer(tr, size, cpu_id); } static void update_last_data(struct trace_array *tr) -- 2.39.5
