Re: [PATCH] tracing/histograms: String compares should not care about signed values

[Masami Hiramatsu]

On Tue, 30 Nov 2021 12:37:36 -0500
Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> From 95f7262b44dc54fed8007cc3db8b39cbd16999c6 Mon Sep 17 00:00:00 2001
> From: "Steven Rostedt (VMware)" <rostedt@xxxxxxxxxxx>
> Date: Tue, 30 Nov 2021 12:31:23 -0500
> Subject: [PATCH] tracing/histograms: String compares should not care about
>  signed values
> 
> When comparing two strings for the "onmatch" histogram trigger, fields
> that are strings use string comparisons, which do not care about being
> signed or not.
> 
> Do not fail to match two string fields if one is unsigned char array and
> the other is a signed char array.
> 
> Link: https://lore.kernel.org/all/20211129123043.5cfd687a@xxxxxxxxxxxxxxxxxx/

Looks good to me.

Review-by: Masami Hiramatsu <mhiramatsu@xxxxxxxxxx>

Thank you,

> 
> Cc: stable@xxxxxxxxxxxxxxxx
> Cc: Tom Zanussi <zanussi@xxxxxxxxxx>
> Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
> Cc: Yafang Shao <laoar.shao@xxxxxxxxx>
> Fixes: b05e89ae7cf3b ("tracing: Accept different type for synthetic event fields")
> Reported-by: Sven Schnelle <svens@xxxxxxxxxxxxx>
> Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
> ---
>  kernel/trace/trace_events_hist.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
> index 9555b8e1d1e3..319f9c8ca7e7 100644
> --- a/kernel/trace/trace_events_hist.c
> +++ b/kernel/trace/trace_events_hist.c
> @@ -3757,7 +3757,7 @@ static int check_synth_field(struct synth_event *event,
>  
>  	if (strcmp(field->type, hist_field->type) != 0) {
>  		if (field->size != hist_field->size ||
> -		    field->is_signed != hist_field->is_signed)
> +		    (!field->is_string && field->is_signed != hist_field->is_signed))
>  			return -EINVAL;
>  	}
>  
> -- 
> 2.31.1
> 


-- 
Masami Hiramatsu <mhiramat@xxxxxxxxxx>