From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B59742F56 for ; Wed, 25 Dec 2024 03:29:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.19 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1735097398; cv=none; b=U2tC/aLvwTJi7z3tnMSWRs8V7HNZJMIUMP5XiOeQmW6dx9oT1DjQ1DMfMVgvx7wGGvjz/SaWz5kDJ4rglJ+4XKu4cCJkwGMiEEXYWQofLFM1F/hnFomHiNM/BUyrtS1vBZNxHHUsxZ+7LLq45dtrE3cU79c5JnrY3p/WtqF0WH4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1735097398; c=relaxed/simple; bh=6KRt73S8jyUxIj99alg4jIGUdSNAt1sqLCp/xyskvtI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=kREv146y7DPGykYg+RBSiJVqyrQrmT6E9wdHslVOlN07g5crhKRl3Jd8qQX3bbmsXgxzme8fbkYr6H7LgqsZeWSz4EvDW/6tohhtunYth1VoCUIorvS8n9gyyqlnN3b4dCLRIrhFxMwLCIBP49w8rCcUDv7S1NksjX4PE4s5I7E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=J+Eb1syB; arc=none smtp.client-ip=192.198.163.19 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="J+Eb1syB" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1735097397; x=1766633397; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=6KRt73S8jyUxIj99alg4jIGUdSNAt1sqLCp/xyskvtI=; b=J+Eb1syB3f3Sab17Rlwjo1xKauFiAcIMyv0EhyqfU2SAEpPNlrEnFfun Gqh72f7wxg91uDZASjKwNdXztxX/8rOcu8DuQJZA01XqrWY0/8ryqwa2g ylmEqpT+n04I48YOF1H0Iqpu8jHttAAW9LrvM+RWI3ttw0SoRUNDFewgf n0+uusdBZQua14IXYVxqvYequY/Yym5chMn88eg0BbLinls040TjL88P4 HAe+WKc1Qj5NRJiUBTI+DXN4Gd5IwpU46xd3SzcsekALZzlyaauz2zN0S +uaUqE09mMqSK1ZrDRpJx6XNU4G29xKqV2dIh/pU8DDEsnUG16FBSRr/K g==; X-CSE-ConnectionGUID: EHnphlidT6+RMO/F+3zD2w== X-CSE-MsgGUID: y1+A8Y/DRi2ZaxUC8OB1kw== X-IronPort-AV: E=McAfee;i="6700,10204,11296"; a="34831962" X-IronPort-AV: E=Sophos;i="6.12,262,1728975600"; d="scan'208";a="34831962" 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> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <9d60933c-4713-4d61-b11f-64d4bb667e04@redhat.com> 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