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Date:   Fri, 21 Aug 2020 09:44:00 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     peterz@infradead.org
Cc:     Sean Christopherson <sean.j.christopherson@intel.com>,
        Andy Lutomirski <luto@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>, linux-kernel@vger.kernel.org,
        Dave Hansen <dave.hansen@intel.com>,
        Chang Seok Bae <chang.seok.bae@intel.com>,
        Sasha Levin <sashal@kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>, kvm@vger.kernel.org,
        Tom Lendacky <thomas.lendacky@amd.com>
Subject: Re: [PATCH] x86/entry/64: Disallow RDPID in paranoid entry if KVM is
 enabled
Message-ID: <20200821074400.GA12181@zn.tnic>
References: <20200821025050.32573-1-sean.j.christopherson@intel.com>
 <20200821072414.GH1362448@hirez.programming.kicks-ass.net>
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On Fri, Aug 21, 2020 at 09:24:14AM +0200, peterz@infradead.org wrote:
> With distro configs that's going to be a guaranteed no_rdpid. Also with
> a grand total of 0 performance numbers that RDPID is even worth it, I'd
> suggest to just unconditionally remove that thing. Simpler code
> all-around.

I was just about to say the same thing - all this dancing around just to
keep RDPID better be backed by numbers, otherwise just remove the damn
thing in that path and use LSL and be done with it.

-- 
Regards/Gruss,
    Boris.

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