From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.19]) (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 7A66D1B040B; Tue, 23 Sep 2025 03:59:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.19 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758599942; cv=none; b=UJyEyLLTc8ESf1W8UvVdQpqEmbKzMSkzUERQQEfhbcMxQFR1T0IjciwhE9Goqvck21g051369spPwZJWX0I8qh0hQH1namS7/zv+Ed1pPbgaEWAtI5EmYsO7AGnMcg0eoR8l8QyeYZKxKleAv2yWtRwP3tXD9Pp+HQD4RCTmNX0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758599942; c=relaxed/simple; bh=pA57IBzvDw/balxYWpPYDXyB2BeYxA6lGokFTJCmhbw=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=pcBPuKC5lSQ8Y0+TO29zG9amxdcsLJ6c3wCLVoZk9QL+t57aiQIEcT5FAvc6uuDbhQoGrGN2au+SFtpqbkmlGspdC6RrMM7ldznM4SE2zPuCCAUmmp7tehofknsz1F9ZXcw5QHeUR5PuXA4FDa3fI6j13pObdvIHmjC9eiuykiM= 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=IXVptUzE; arc=none smtp.client-ip=198.175.65.19 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="IXVptUzE" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1758599940; x=1790135940; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=pA57IBzvDw/balxYWpPYDXyB2BeYxA6lGokFTJCmhbw=; b=IXVptUzEyHw6Rs8Avm++1L77vGBflo4EysLD0WLqLO1MTxyZMjbwfaGY Nl7ChXg/3VTzexLhIu4ju1snXCjTFZ/UrJYw8AIW39Gh9Vjt4yR4kHEz7 uS3ujEGAXs5qNnuBNbakkBxITHW5rcp/0PxBpXazcn+JGudh9/I0fI255 SMpC0e+Dp8pwZSRuYvVF8sTutP4tYu+Ch+yvGz5zjyiTu04onGOZvv5WZ aBDNboZwd1XLdaL4relCnMv2LOWmGfbxRZnmt7njY9llAz1D+EmCXgqtR ShU4y0urG24+Djri958r59M7NpyE05SAYGxhFPze81jh1DUOZxSchKiZz g==; X-CSE-ConnectionGUID: K/fD0biTQG+BQT5ehCYSyQ== X-CSE-MsgGUID: RgLmVzZLQS6JMAqOG0ambw== X-IronPort-AV: E=McAfee;i="6800,10657,11561"; a="60760060" X-IronPort-AV: E=Sophos;i="6.18,286,1751266800"; d="scan'208";a="60760060" Received: from orviesa009.jf.intel.com ([10.64.159.149]) by orvoesa111.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Sep 2025 20:59:00 -0700 X-CSE-ConnectionGUID: mR1wRD7/SCKJRQ2OddijQA== X-CSE-MsgGUID: jfLdrXLIQPCwjrHzpAriiQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.18,286,1751266800"; d="scan'208";a="176234743" Received: from xiaoyaol-hp-g830.ccr.corp.intel.com (HELO [10.124.238.14]) ([10.124.238.14]) by orviesa009-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Sep 2025 20:58:59 -0700 Message-ID: <064c1240-e7f0-4061-a43a-9d05a46953a0@intel.com> Date: Tue, 23 Sep 2025 11:58:55 +0800 Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 1/2] KVM: x86: Add helper to retrieve current value of user return MSR To: Sean Christopherson , Paolo Bonzini Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Hou Wenlong , Lai Jiangshan References: <20250919213806.1582673-1-seanjc@google.com> <20250919213806.1582673-2-seanjc@google.com> Content-Language: en-US From: Xiaoyao Li In-Reply-To: <20250919213806.1582673-2-seanjc@google.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 9/20/2025 5:38 AM, Sean Christopherson wrote: > From: Hou Wenlong > > In the user return MSR support, the cached value is always the hardware > value of the specific MSR. Therefore, add a helper to retrieve the > cached value, which can replace the need for RDMSR, for example, to > allow SEV-ES guests to restore the correct host hardware value without > using RDMSR. > > Cc: stable@vger.kernel.org > Signed-off-by: Hou Wenlong > [sean: drop "cache" from the name, make it a one-liner, tag for stable] > Signed-off-by: Sean Christopherson Reviewed-by: Xiaoyao Li