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Sender: Ingo Molnar <mingo.kernel.org@gmail.com>
Date:   Sat, 6 Aug 2022 21:00:50 +0200
From:   Ingo Molnar <mingo@kernel.org>
To:     Kim Phillips <kim.phillips@amd.com>
Cc:     bp@alien8.de, x86@kernel.org, peterz@infradead.org, bp@suse.de,
        bpf@vger.kernel.org, jpoimboe@redhat.com,
        andrew.cooper3@citrix.com, linux-kernel@vger.kernel.org,
        thomas.lendacky@amd.com
Subject: Re: [PATCH v2] x86/bugs: Enable STIBP for IBPB mitigated RetBleed
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 <20220805215009.498407-1-kim.phillips@amd.com>
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* Kim Phillips <kim.phillips@amd.com> wrote:

>  			Speculative Code Execution with Return Instructions)
>  			vulnerability.
>  
> +			AMD-based unret and ibpb mitigations alone do not stop
> +			sibling threads influencing the predictions of other sibling
> +			threads.  For that reason, we use STIBP on processors
> +			that support it, and mitigate SMT on processors that don't.

>  	 * retbleed_select_mitigation(); specifically the STIBP selection is
> -	 * forced for UNRET.
> +	 * forced for UNRET or IBPB.

Nit: could you please capitalize the acronyms & instruction names 
consistently? Human eyesight is case sensitive.

Ie. it should be UNRET and IBPB everywhere.

Thanks,

	Ingo