From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 64092C2BB1D for ; Wed, 15 Apr 2020 02:51:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 403AA20787 for ; Wed, 15 Apr 2020 02:51:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388167AbgDOCvJ (ORCPT ); Tue, 14 Apr 2020 22:51:09 -0400 Received: from mga01.intel.com ([192.55.52.88]:1607 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730346AbgDOCvH (ORCPT ); Tue, 14 Apr 2020 22:51:07 -0400 IronPort-SDR: FDcLjSRNUQGMlO6tN1lEKPA4uyVIi972AacZmK5IA6iTWQrx0EkB5TQYCDfkYhCmsWKUgNXIaV m7AWqx+rWx1A== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Apr 2020 19:51:05 -0700 IronPort-SDR: 5lXNmwCXudgWW8KsmxKVXjnbctzEfYwxrspNAggrcqJvmWIEruLwb4wz1c845I4voEH0SJWFnK 884hRA6oncJw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.72,385,1580803200"; d="scan'208";a="272027224" Received: from sjchrist-coffee.jf.intel.com (HELO linux.intel.com) ([10.54.74.202]) by orsmga008.jf.intel.com with ESMTP; 14 Apr 2020 19:51:05 -0700 Date: Tue, 14 Apr 2020 19:51:05 -0700 From: Sean Christopherson To: Jon Cargille Cc: Paolo Bonzini , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Eric Northup , Eric Northup Subject: Re: [PATCH 1/1] KVM: pass through CPUID(0x80000006) Message-ID: <20200415025105.GE12547@linux.intel.com> References: <20200415012320.236065-1-jcargill@google.com> <20200415023726.GD12547@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200415023726.GD12547@linux.intel.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Tue, Apr 14, 2020 at 07:37:26PM -0700, Sean Christopherson wrote: > On Tue, Apr 14, 2020 at 06:23:20PM -0700, Jon Cargille wrote: > > From: Eric Northup > > > > Return L2 cache and TLB information to guests. > > They could have been set before, but the defaults that KVM returns will be > > necessary for usermode that doesn't supply their own CPUID tables. > > I don't follow the changelog. The code makes sense, but I don't understand > the justification. This only affects KVM_GET_SUPPORTED_CPUID, i.e. what's > advertised to userspace, it doesn't directly change CPUID emulation in any > way. The "They could have been set before" blurb is especially confusing. > > I assume you want to say something like: > > Return the host's L2 cache and TLB information for CPUID.0x80000006 > instead of zeroing out the entry as part of KVM_GET_SUPPORTED_CPUID. > This allows a userspace VMM to feed KVM_GET_SUPPORTED_CPUID's output > directly into KVM_SET_CPUID2 (without breaking the guest). > > > Signed-off-by: Eric Northup > > Signed-off-by: Eric Northup > > Signed-off-by: Jon Cargille > > Signed-off-by: Jim Mattson > > Jim's tag is unnecessary, unless he was a middleman between Eric and Jon, > in which case Jim's tag should also come between Eric's and Jon's. > > Only one of Eric's signoffs is needed (the one that matches the From: tag, > i.e. is the official author). I'm guessing Google would prefer the author > to be the @google.com address. Ah, Eric's @google.com mail bounced. Maybe do: Signed-off-by: Eric Northup (Google) to clarify the work was done for Google without having a double signoff and/or a dead email.