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X-CSE-ConnectionGUID: KLl2qQ/PQbW8hhQW08XFfw== X-CSE-MsgGUID: 3e0FpVyBQ0Gvz0mncaQUKw== X-IronPort-AV: E=McAfee;i="6800,10657,11717"; a="98987264" X-IronPort-AV: E=Sophos;i="6.21,320,1763452800"; d="scan'208";a="98987264" Received: from orviesa010.jf.intel.com ([10.64.159.150]) by fmvoesa101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Mar 2026 15:00:20 -0800 X-CSE-ConnectionGUID: JRx467CfT6WSmwPKcEMEpA== X-CSE-MsgGUID: q/vFXteBTqKi7n6ukoqVRw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.21,320,1763452800"; d="scan'208";a="217034829" Received: from cmdeoliv-mobl4.amr.corp.intel.com (HELO [10.125.108.103]) ([10.125.108.103]) by orviesa010-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Mar 2026 15:00:19 -0800 Message-ID: <567d39b9-d595-4ccc-a344-4396c5320f74@intel.com> Date: Mon, 2 Mar 2026 15:00:23 -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 1/7] x86/cpufeatures: Add X86_FEATURE_AMD_RMPOPT feature flag To: Ashish Kalra , tglx@kernel.org, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, seanjc@google.com, peterz@infradead.org, thomas.lendacky@amd.com, herbert@gondor.apana.org.au, davem@davemloft.net, ardb@kernel.org Cc: pbonzini@redhat.com, aik@amd.com, Michael.Roth@amd.com, KPrateek.Nayak@amd.com, Tycho.Andersen@amd.com, Nathan.Fontenot@amd.com, jackyli@google.com, pgonda@google.com, rientjes@google.com, jacobhxu@google.com, xin@zytor.com, pawan.kumar.gupta@linux.intel.com, babu.moger@amd.com, dyoung@redhat.com, nikunj@amd.com, john.allen@amd.com, darwi@linutronix.de, linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org, kvm@vger.kernel.org, linux-coco@lists.linux.dev References: <219ebbd57ac1d99fc5ea055431f7a8396021c2c2.1772486459.git.ashish.kalra@amd.com> From: Dave Hansen Content-Language: en-US Autocrypt: addr=dave.hansen@intel.com; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 3/2/26 13:35, Ashish Kalra wrote: > From: Ashish Kalra > > Add a flag indicating whether RMPOPT instruction is supported. > > RMPOPT is a new instruction designed to minimize the performance > overhead of RMP checks on the hypervisor and on non-SNP guests by > allowing RMP checks to be skipped when 1G regions of memory are known > not to contain any SEV-SNP guest memory. > > For more information on the RMPOPT instruction, see the AMD64 RMPOPT > technical documentation. [1] Reviewed-by: Dave Hansen