linux-kernel - Re: [RFC PATCH v2 11/20] objtool: Flesh out warning related to pv

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Message-ID: <20230728153334.myvh5sxppvjzd3oz@treble>
Date:   Fri, 28 Jul 2023 10:33:34 -0500
From:   Josh Poimboeuf <jpoimboe@...nel.org>
To:     Valentin Schneider <vschneid@...hat.com>
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Subject: Re: [RFC PATCH v2 11/20] objtool: Flesh out warning related to
 pv_ops[] calls

On Thu, Jul 20, 2023 at 05:30:47PM +0100, Valentin Schneider wrote:
> I had to look into objtool itself to understand what this warning was
> about; make it more explicit.
> 
> Signed-off-by: Valentin Schneider <vschneid@...hat.com>
> ---
>  tools/objtool/check.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tools/objtool/check.c b/tools/objtool/check.c
> index 8936a05f0e5ac..d308330f2910e 100644
> --- a/tools/objtool/check.c
> +++ b/tools/objtool/check.c
> @@ -3360,7 +3360,7 @@ static bool pv_call_dest(struct objtool_file *file, struct instruction *insn)
>  
>  	list_for_each_entry(target, &file->pv_ops[idx].targets, pv_target) {
>  		if (!target->sec->noinstr) {
> -			WARN("pv_ops[%d]: %s", idx, target->name);
> +			WARN("pv_ops[%d]: indirect call to %s() leaves .noinstr.text section", idx, target->name);
>  			file->pv_ops[idx].clean = false;

This is an improvement, though I think it still results in two warnings,
with the second not-so-useful warning happening in validate_call().

Ideally it would only show a single warning, I guess that would need a
little bit of restructuring the code.

-- 
Josh