From 2cf9733891a460a16a209fcc20fbd138605b13b8 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Fri, 11 Oct 2024 16:52:24 -0400 Subject: [PATCH] ring-buffer: Fix refcount setting of boot mapped buffers A ring buffer which has its buffered mapped at boot up to fixed memory should not be freed. Other buffers can be. The ref counting setup was wrong for both. It made the not mapped buffers ref count have zero, and the boot mapped buffer a ref count of 1. But an normally allocated buffer should be 1, where it can be removed. Keep the ref count of a normal boot buffer with its setup ref count (do not decrement it), and increment the fixed memory boot mapped buffer's ref count. Cc: Mathieu Desnoyers Link: https://lore.kernel.org/20241011165224.33dd2624@gandalf.local.home Fixes: e645535a954ad ("tracing: Add option to use memmapped memory for trace boot instance") Reviewed-by: Masami Hiramatsu (Google) Signed-off-by: Steven Rostedt (Google) --- kernel/trace/trace.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 1c69ca1f1088..a8f52b6527ca 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -10621,10 +10621,10 @@ __init static void enable_instances(void) * cannot be deleted by user space, so keep the reference * to it. */ - if (start) + if (start) { tr->flags |= TRACE_ARRAY_FL_BOOT; - else - trace_array_put(tr); + tr->ref++; + } while ((tok = strsep(&curr_str, ","))) { early_enable_events(tr, tok, true);