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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A2F33C4332F for ; Wed, 14 Dec 2022 21:28:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229730AbiLNV25 (ORCPT ); Wed, 14 Dec 2022 16:28:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60872 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229500AbiLNV24 (ORCPT ); Wed, 14 Dec 2022 16:28:56 -0500 Received: from mga18.intel.com (mga18.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A7917316; Wed, 14 Dec 2022 13:28:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1671053335; x=1702589335; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=BfyZ0wbnXjjKIR9uhDPYIesZqV9+mxpLj1ZhNhI6kxY=; b=dALwBPuE6ZF1B4iHZeRrdFgFwBAG0qf7aHiUw4IMRfQGSnjeYvwUVzur csTIYIUXh2qo+XAtNawXvzb7jZkkMkrlZsFezH+KPaAyzeoFaU9s3nNn6 +gbjDtd9Mi/7o4+jwVX83JSmQLkc68mFu2IBfcQD6LKqOC5wyqWIEQ3pj diueNQMzy7dKoqki7vnzjmQ1/4OiEWCPcCwdY1Z9HOy9R+CGlSq5cw9gI k9hPHTM3HunjB6vFqmnHI2irc/A65f/9uXUlbN5FfPUJkOlJrnbWRrYzC ZxEyzdbi/ZBym1FqADEFoVsaMau3n3AMaRr7opwOtqlSuewQzgH8Bd/rl w==; X-IronPort-AV: E=McAfee;i="6500,9779,10561"; a="301927111" X-IronPort-AV: E=Sophos;i="5.96,245,1665471600"; d="scan'208";a="301927111" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Dec 2022 13:28:55 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10561"; a="599341833" X-IronPort-AV: E=Sophos;i="5.96,245,1665471600"; d="scan'208";a="599341833" Received: from ranerica-svr.sc.intel.com ([172.25.110.23]) by orsmga003.jf.intel.com with ESMTP; 14 Dec 2022 13:28:54 -0800 Date: Wed, 14 Dec 2022 13:37:07 -0800 From: Ricardo Neri To: Zhang Chen Cc: x86@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Chao Gao , Pawan Gupta , Paolo Bonzini , Sean Christopherson , "H. Peter Anvin" , Dave Hansen , Borislav Petkov , Ingo Molnar , Thomas Gleixner Subject: Re: [RFC PATCH 3/9] KVM: x86: Add a kvm-only leaf for BHI_CTRL Message-ID: <20221214213707.GC16072@ranerica-svr.sc.intel.com> References: <20221210160046.2608762-1-chen.zhang@intel.com> <20221210160046.2608762-4-chen.zhang@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221210160046.2608762-4-chen.zhang@intel.com> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Sun, Dec 11, 2022 at 12:00:40AM +0800, Zhang Chen wrote: > KVM needs to check if guests can see BHI_CTRL. If a guest is using > BHB-clearing sequence and cannot see BHI_CTRL and the host enumerates BHI, > KVM is responsible for setting BHI_DIS_S for the guest. > > This allows VM migration from parts doesn't enumerate BHI to those > that enumerate BHI. Similar comment as in patch 2.