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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C1033E7718B for ; Wed, 25 Dec 2024 03:30:49 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tQI60-0002rA-SX; Tue, 24 Dec 2024 22:30:04 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tQI5y-0002qz-OQ for qemu-devel@nongnu.org; Tue, 24 Dec 2024 22:30:03 -0500 Received: from mgamail.intel.com ([192.198.163.19]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tQI5v-0001LS-NA for qemu-devel@nongnu.org; Tue, 24 Dec 2024 22:30:02 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1735097400; x=1766633400; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=6KRt73S8jyUxIj99alg4jIGUdSNAt1sqLCp/xyskvtI=; b=O7rL09kKI2RrdA2R5otIZQNRHUmewnE3Uo9HphEnPShZGrIfsEf6J4oU tge22/4X+xf4E8lLjPCOo7Od/2EuHkVIZvosvUvSuU2Lonp2eLyDvZezI s3xOsLOfCmAzs5zWgqRLLWsDLNb1Uousj5JFgd6lBwPErmGeRv5mITHJ3 7FkB6SCGQr49dO+jToAwCalh3v8MPdqdiCZJEunwZZHoeOzx/QaWLMAt8 N+txRnn0fzctIjDHcmrK+qemWQo9hxgpqGXsewkbEisMEs97ccfe7+5eq yxVBEWJIzMOZtHP+28ziOUNv4RWtl9OZXp48ohqpWxCPdUqW0upwSg8YW g==; X-CSE-ConnectionGUID: RoRifizRTiiS8vic1ku3Bg== X-CSE-MsgGUID: DbSPKMM4TUawsfKzrelH5Q== X-IronPort-AV: E=McAfee;i="6700,10204,11296"; a="34831965" X-IronPort-AV: E=Sophos;i="6.12,262,1728975600"; d="scan'208";a="34831965" Received: from orviesa005.jf.intel.com ([10.64.159.145]) by fmvoesa113.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Dec 2024 19:29:56 -0800 X-CSE-ConnectionGUID: qpRstatgSFupSRXCMiNDug== X-CSE-MsgGUID: 3kiwq8OCSB+FFsUsg79H2Q== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.12,224,1728975600"; d="scan'208";a="104623068" Received: from liuzhao-optiplex-7080.sh.intel.com (HELO localhost) ([10.239.160.39]) by orviesa005.jf.intel.com with ESMTP; 24 Dec 2024 19:29:53 -0800 Date: Wed, 25 Dec 2024 11:48:35 +0800 From: Zhao Liu To: Paolo Bonzini Cc: Richard Henderson , Eduardo Habkost , "Michael S . Tsirkin" , Marcel Apfelbaum , Marcelo Tosatti , Tao Su , Xiaoyao Li , Pankaj Gupta , Zide Chen , qemu-devel@nongnu.org, kvm@vger.kernel.org Subject: Re: [PATCH v5 04/11] target/i386/kvm: Only save/load kvmclock MSRs when kvmclock enabled Message-ID: References: <20241106030728.553238-1-zhao1.liu@intel.com> <20241106030728.553238-5-zhao1.liu@intel.com> <9d60933c-4713-4d61-b11f-64d4bb667e04@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <9d60933c-4713-4d61-b11f-64d4bb667e04@redhat.com> Received-SPF: pass client-ip=192.198.163.19; envelope-from=zhao1.liu@intel.com; helo=mgamail.intel.com X-Spam_score_int: -44 X-Spam_score: -4.5 X-Spam_bar: ---- X-Spam_report: (-4.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.133, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Tue, Dec 24, 2024 at 04:31:28PM +0100, Paolo Bonzini wrote: > Date: Tue, 24 Dec 2024 16:31:28 +0100 > From: Paolo Bonzini > Subject: Re: [PATCH v5 04/11] target/i386/kvm: Only save/load kvmclock MSRs > when kvmclock enabled > > On 11/6/24 04:07, Zhao Liu wrote: > > MSR_KVM_SYSTEM_TIME and MSR_KVM_WALL_CLOCK are attached with the (old) > > kvmclock feature (KVM_FEATURE_CLOCKSOURCE). > > > > So, just save/load them only when kvmclock (KVM_FEATURE_CLOCKSOURCE) is > > enabled. > > > > Signed-off-by: Zhao Liu > > > > The MSRs contains the same values as the "new" pair; QEMU only has to > save/restore one of them but the code should be active for both feature bits > and thus use > > + if (env->env.features[FEAT_KVM] & (CPUID_KVM_CLOCK | > + CPUID_KVM_CLOCK2)) { > This is the correct way, thanks. Regards, Zhao