linux-kernel - Re: [PATCH v2] objtool: Support multiple rodata sections.

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Message-ID: <20180828165829.woylt7lgoj3qz5up@treble>
Date:   Tue, 28 Aug 2018 11:58:29 -0500
From:   Josh Poimboeuf <jpoimboe@...hat.com>
To:     Allan Xavier <allan.x.xavier@...cle.com>
Cc:     Peter Zijlstra <peterz@...radead.org>, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2] objtool: Support multiple rodata sections.

On Fri, Aug 03, 2018 at 07:40:40PM +0100, Allan Xavier wrote:
> +static void mark_rodata(struct objtool_file *file)
> +{
> +	struct section *sec;
> +	bool found = false;
> +	static const char *str1 = ".str1.";
> +	const int str1len = strlen(str1) + 1;
> +

A comment here would help, explaining that this looks for both .rodata
and .rodata.func_name sections (when using -fdata-sections).

> +	for_each_sec(file, sec) {
> +		if (strstr(sec->name, ".rodata") == sec->name) {
> +			char *str1pos = sec->name + strlen(sec->name) - str1len;
> +
> +			/* Skips over .rodata.str1.1 and .rodata.str.1.8 */
> +			if (strstr(sec->name, str1) != str1pos) {
> +				sec->rodata = true;
> +				found = true;
> +			}
> +		}
> +	}

This could be simplified and made more readable with something like:

	for_each_sec(file, sec) {
		if (!strncmp(sec->name, ".rodata", 7) &&
		    !strstr(sec->name, ".str1.") {
		    	sec->rodata = true;
			found = true;
		}
	}

-- 
Josh