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b=B3dbXVhS9tRKxrDMXbl9hA1HyVJ+vyaJkKHcq1r3OwbSS9xZ9uji1PqbuqOKXxgb7LT9znFoW4TV79MjyoWZcuP06XEQDpVllPHxTlpEtro+yqqcD9ClHnXa5ubpGDqtLgZYgYrrSVk38KHnNLq2V6RFLFvr1YAFul1rDxnGBsw= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=amd.com; Received: from BL3PR12MB9049.namprd12.prod.outlook.com (2603:10b6:208:3b8::21) by SN7PR12MB6983.namprd12.prod.outlook.com (2603:10b6:806:261::20) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9031.24; Wed, 20 Aug 2025 23:23:40 +0000 Received: from BL3PR12MB9049.namprd12.prod.outlook.com ([fe80::ae6a:9bdd:af5b:e9ad]) by BL3PR12MB9049.namprd12.prod.outlook.com ([fe80::ae6a:9bdd:af5b:e9ad%6]) with mapi id 15.20.8989.018; Wed, 20 Aug 2025 23:23:39 +0000 Message-ID: <7eed1970-4e7d-4b3a-a3c1-198b0a6521d5@amd.com> Date: Wed, 20 Aug 2025 18:23:35 -0500 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v9 2/2] KVM: SEV: Add SEV-SNP CipherTextHiding support To: Randy Dunlap , corbet@lwn.net, seanjc@google.com, pbonzini@redhat.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, thomas.lendacky@amd.com, herbert@gondor.apana.org Cc: akpm@linux-foundation.org, rostedt@goodmis.org, paulmck@kernel.org, michael.roth@amd.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org References: <95abc49edfde36d4fb791570ea2a4be6ad95fd0d.1755721927.git.ashish.kalra@amd.com> <5dff05c1-474e-4fff-a19b-7c17b4db6173@infradead.org> Content-Language: en-US From: "Kalra, Ashish" In-Reply-To: <5dff05c1-474e-4fff-a19b-7c17b4db6173@infradead.org> Content-Type: text/plain; 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>> + >> + if (sev_is_snp_ciphertext_hiding_supported()) >> + init_args.max_snp_asid = min(nr_ciphertext_hiding_asids, >> + min_sev_asid - 1); >> + >> if (sev_platform_init(&init_args)) >> sev_supported = sev_es_supported = sev_snp_supported = false; >> else if (sev_snp_supported) >> sev_snp_supported = is_sev_snp_initialized(); >> + >> + if (sev_snp_supported) >> + nr_ciphertext_hiding_asids = init_args.max_snp_asid; >> + >> + /* >> + * If ciphertext hiding is enabled, the joint SEV-ES/SEV-SNP >> + * ASID range is partitioned into separate SEV-ES and SEV-SNP >> + * ASID ranges, with the SEV-SNP range being [1..max_snp_asid] >> + * and the SEV-ES range being [max_snp_asid..max_sev_es_asid]. > > [max_snp_asid + 1..max_sev_es_asid] > ? Yes. Thanks, Ashish > >> + * Note, SEV-ES may effectively be disabled if all ASIDs from >> + * the joint range are assigned to SEV-SNP. >> + */