tracing: Check the return value of tracing_update_buffers()

[PATCH] tracing: Check the return value of tracing_update_buffers()

Posted by Steven Rostedt 1 month ago

From: Steven Rostedt <rostedt@goodmis.org>

In the very unlikely event that tracing_update_buffers() fails in
trace_printk_init_buffers(), report the failure so that it is known.

Link: https://lore.kernel.org/all/20220917020353.3836285-1-floridsleeves@gmail.com/

Suggested-by: Li Zhong <floridsleeves@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
---
 kernel/trace/trace.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 2d387d56dcd4..1722e01e2238 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3418,9 +3418,10 @@ void trace_printk_init_buffers(void)
 	pr_warn("**********************************************************\n");
 
 	/* Expand the buffers to set size */
-	tracing_update_buffers(&global_trace);
-
-	buffers_allocated = 1;
+	if (tracing_update_buffers(&global_trace) < 0)
+		pr_err("Failed to expand tracing buffers for trace_printk() calls\n");
+	else
+		buffers_allocated = 1;
 
 	/*
 	 * trace_printk_init_buffers() can be called by modules.
-- 
2.51.0

Re: [PATCH] tracing: Check the return value of tracing_update_buffers()

Posted by Masami Hiramatsu (Google) 4 weeks, 1 day ago

On Wed, 7 Jan 2026 16:15:10 -0500
Steven Rostedt <rostedt@goodmis.org> wrote:

> From: Steven Rostedt <rostedt@goodmis.org>
> 
> In the very unlikely event that tracing_update_buffers() fails in
> trace_printk_init_buffers(), report the failure so that it is known.
> 
> Link: https://lore.kernel.org/all/20220917020353.3836285-1-floridsleeves@gmail.com/

Good catch! Looks good to me.

Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Thanks,

> 
> Suggested-by: Li Zhong <floridsleeves@gmail.com>
> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
> ---
>  kernel/trace/trace.c | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
> index 2d387d56dcd4..1722e01e2238 100644
> --- a/kernel/trace/trace.c
> +++ b/kernel/trace/trace.c
> @@ -3418,9 +3418,10 @@ void trace_printk_init_buffers(void)
>  	pr_warn("**********************************************************\n");
>  
>  	/* Expand the buffers to set size */
> -	tracing_update_buffers(&global_trace);
> -
> -	buffers_allocated = 1;
> +	if (tracing_update_buffers(&global_trace) < 0)
> +		pr_err("Failed to expand tracing buffers for trace_printk() calls\n");
> +	else
> +		buffers_allocated = 1;
>  
>  	/*
>  	 * trace_printk_init_buffers() can be called by modules.
> -- 
> 2.51.0
> 
> 


-- 
Masami Hiramatsu (Google) <mhiramat@kernel.org>