Subject: Re: [PATCH] perf llvm: Fix error return code in llvm__compile_bpf()

From: Arnaldo Carvalho de Melo <[email-masked]>
Date: Thu, 1 Jul 2021 14:20:13 -0300

Em Wed, Jun 09, 2021 at 07:59:45PM +0800, Zhihao Cheng escreveu:
> Fix to return a negative error code from the error handling
> case instead of 0, as done elsewhere in this function.

I checked and llvm__compile_bpf() returns -errno, so I'll change this to
instead set err to -ENOMEM just before the if (asprintf)(), ok?

- Arnaldo
 
> Fixes: cb76371441d098 ("perf llvm: Allow passing options to llc ...")
> Fixes: 5eab5a7ee032ac ("perf llvm: Display eBPF compiling command ...")
> Reported-by: Hulk Robot <[email-masked]>
> Signed-off-by: Zhihao Cheng <[email-masked]>
> ---
>  tools/perf/util/llvm-utils.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/tools/perf/util/llvm-utils.c b/tools/perf/util/llvm-utils.c
> index 3ceaf7ef3301..2de02639fb67 100644
> --- a/tools/perf/util/llvm-utils.c
> +++ b/tools/perf/util/llvm-utils.c
> @@ -504,8 +504,9 @@ int llvm__compile_bpf(const char *path, void **p_obj_buf,
>  			goto errout;
>  		}
>  
> -		if (asprintf(&pipe_template, "%s -emit-llvm | %s -march=bpf %s -filetype=obj -o -",
> -			      template, llc_path, opts) < 0) {
> +		err = asprintf(&pipe_template, "%s -emit-llvm | %s -march=bpf %s -filetype=obj -o -",
> +			       template, llc_path, opts);
> +		if (err < 0) {
>  			pr_err("ERROR:\tnot enough memory to setup command line\n");
>  			goto errout;
>  		}
> @@ -524,7 +525,8 @@ int llvm__compile_bpf(const char *path, void **p_obj_buf,
>  
>  	pr_debug("llvm compiling command template: %s\n", template);
>  
> -	if (asprintf(&command_echo, "echo -n \"%s\"", template) < 0)
> +	err = asprintf(&command_echo, "echo -n \"%s\"", template);
> +	if (err < 0)
>  		goto errout;
>  
>  	err = read_from_pipe(command_echo, (void **) &command_out, NULL);
> -- 
> 2.31.1
> 

-- 

- Arnaldo