linux-kernel - Re: [PATCH 13/14] x86: BHI stubs

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Message-ID: <20240928013736.tirg3rivjf2nb3am@treble>
Date: Fri, 27 Sep 2024 18:37:36 -0700
From: Josh Poimboeuf <jpoimboe@...nel.org>
To: Peter Zijlstra <peterz@...radead.org>
Cc: x86@...nel.org, linux-kernel@...r.kernel.org, alyssa.milburn@...el.com,
	scott.d.constable@...el.com, joao@...rdrivepizza.com,
	andrew.cooper3@...rix.com, jose.marchesi@...cle.com,
	hjl.tools@...il.com, ndesaulniers@...gle.com,
	samitolvanen@...gle.com, nathan@...nel.org, ojeda@...nel.org,
	kees@...nel.org, alexei.starovoitov@...il.com
Subject: Re: [PATCH 13/14] x86: BHI stubs

On Fri, Sep 27, 2024 at 09:49:09PM +0200, Peter Zijlstra wrote:
> +static void *bhi_args_1(u8 args, void *addr)
> +{
> +	u8 bytes[5];
> +
> +	for (int i = 0; i < 6; i++) {
> +		if (args != BIT(i))
> +			continue;
> +
> +		bytes[0] = 0x2e;
> +		memcpy(&bytes[1], &__bhi_args_6c1[i], 4);
> +
> +		text_poke_early(addr, bytes, 5);
> +
> +		return NULL;

I assume there's some good reason this doesn't return a pointer to the
code like the others?

-- 
Josh