Date:   Wed, 22 Feb 2023 13:32:33 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     KP Singh <kpsingh@kernel.org>
Cc:     Pawan Gupta <pawan.kumar.gupta@linux.intel.com>,
        linux-kernel@vger.kernel.org, pjt@google.com, evn@google.com,
        jpoimboe@kernel.org, tglx@linutronix.de, x86@kernel.org,
        hpa@zytor.com, peterz@infradead.org, kim.phillips@amd.com,
        alexandre.chartre@oracle.com, daniel.sneddon@linux.intel.com,
        corbet@lwn.net, bp@suse.de, linyujun809@huawei.com,
        jmattson@google.com,
        =?utf-8?B?Sm9zw6k=?= Oliveira <joseloliveira11@gmail.com>,
        Rodrigo Branco <rodrigo@kernelhacking.com>,
        Alexandra Sandulescu <aesa@google.com>, stable@vger.kernel.org
Subject: Re: [PATCH v2 1/2] x86/speculation: Allow enabling STIBP with legacy
 IBRS
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On Tue, Feb 21, 2023 at 09:49:57PM -0800, KP Singh wrote:
> That is a bit more complicated as, for now, the user is not really
> exposed to STIBP explicitly yet.

Remember that we're exposing the normal user to a gazillion switches
already. And not every user has done a PhD in hw vulns like we were
forced to in the last, at least 5, years.

So whatever you do, you should try to make it work automatic - if
possible - and DTRT - i.e., sane defaults.

Every new functionality added to that madness needs a proper
justification.

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette