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Date:   Fri, 21 Aug 2020 22:02:07 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     hpa@zytor.com
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Borislav Petkov <bp@alien8.de>,
        Sean Christopherson <sean.j.christopherson@intel.com>,
        Andy Lutomirski <luto@kernel.org>,
        Ingo Molnar <mingo@redhat.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org, Dave Hansen <dave.hansen@intel.com>,
        Chang Seok Bae <chang.seok.bae@intel.com>,
        Sasha Levin <sashal@kernel.org>, 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
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On Fri, Aug 21, 2020 at 12:55:53PM -0700, hpa@zytor.com wrote:

> It is hardly going to be a performance difference for paranoid entry,
> which is hopefully rare enough that it falls into the noise.

Try perf some day ;-)

But yeah, given the utter trainwreck that NMIs are anyway, this is all
not going to matter much.