Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932861AbcJ2MZx (ORCPT ); Sat, 29 Oct 2016 08:25:53 -0400 Received: from mail.skyhub.de ([78.46.96.112]:55681 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755088AbcJ2MZv (ORCPT ); Sat, 29 Oct 2016 08:25:51 -0400 Date: Sat, 29 Oct 2016 14:25:48 +0200 From: Borislav Petkov To: Paolo Bonzini Cc: Piotr Luc , kvm@vger.kernel.org, he chen , linux-kernel@vger.kernel.org, tglx@linutronix.de, x86@kernel.org, hpa@zytor.com, mingo@redhat.com, Luwei Kang , rkrcmar@redhat.com Subject: Re: [PATCH] x86/cpuid: expose AVX512_4VNNIW and AVX512_4FMAPS features to kvm guest Message-ID: <20161029122548.niyvh2q3kuvyqwo3@pd.tnic> References: <1477645960-6898-1-git-send-email-he.chen@linux.intel.com> <1477649272.17668.7.camel@intel.com> <5c00fdf0-a5a4-7a78-4ed8-8ae3ef710a68@redhat.com> <20161028110834.svzzs5hftg3bybiz@pd.tnic> <20161028122123.24i3synevehn6r3p@pd.tnic> <425702906.9319122.1477743677017.JavaMail.zimbra@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <425702906.9319122.1477743677017.JavaMail.zimbra@redhat.com> User-Agent: NeoMutt/20161014 (1.7.1) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 594 Lines: 19 On Sat, Oct 29, 2016 at 08:21:17AM -0400, Paolo Bonzini wrote: > Currently none of the bits in CPUID[7,0].edx is ever masked by the host, so > this would be enough. If we ever need to do some masking, I guess I'll > practice my puss-in-boots look and submit a patch to add CPUID[7,0] back > as a separate cpufeature entr. I don't understand - why can't it be filtered here if needed? I.e., return edx & KVM_CPUID_EDX_7_MASK; or so? Btw, we already have a cpuid_edx() helper in arch/x86/include/asm/processor.h -- Regards/Gruss, Boris. ECO tip #101: Trim your mails when you reply.