From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qk0-f199.google.com (mail-qk0-f199.google.com [209.85.220.199]) by kanga.kvack.org (Postfix) with ESMTP id D06916B0387 for ; Mon, 17 Jul 2017 17:11:09 -0400 (EDT) Received: by mail-qk0-f199.google.com with SMTP id o5so871220qki.2 for ; Mon, 17 Jul 2017 14:11:09 -0700 (PDT) Received: from NAM01-BN3-obe.outbound.protection.outlook.com (mail-bn3nam01on0050.outbound.protection.outlook.com. [104.47.33.50]) by mx.google.com with ESMTPS id r36si251357qtc.252.2017.07.17.14.11.08 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 17 Jul 2017 14:11:09 -0700 (PDT) From: Tom Lendacky Subject: [PATCH v10 05/38] x86/CPU/AMD: Handle SME reduction in physical address size Date: Mon, 17 Jul 2017 16:10:02 -0500 Message-Id: <593c037a3cad85ba92f3d061ffa7462e9ce3531d.1500319216.git.thomas.lendacky@amd.com> In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain Sender: owner-linux-mm@kvack.org List-ID: To: x86@kernel.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-efi@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, kvm@vger.kernel.org, kasan-dev@googlegroups.com Cc: =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Arnd Bergmann , Jonathan Corbet , Matt Fleming , Konrad Rzeszutek Wilk , Andrey Ryabinin , Ingo Molnar , Borislav Petkov , Andy Lutomirski , "H. Peter Anvin" , Paolo Bonzini , Alexander Potapenko , Thomas Gleixner , Dmitry Vyukov , Rik van Riel , Larry Woodman , Dave Young , Toshimitsu Kani , "Michael S. Tsirkin" , Brijesh Singh When System Memory Encryption (SME) is enabled, the physical address space is reduced. Adjust the x86_phys_bits value to reflect this reduction. Reviewed-by: Borislav Petkov Signed-off-by: Tom Lendacky --- arch/x86/kernel/cpu/amd.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-) diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index 7f658d0..e41670e 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -614,21 +614,23 @@ static void early_init_amd(struct cpuinfo_x86 *c) set_cpu_bug(c, X86_BUG_AMD_E400); /* - * BIOS support is required for SME. If BIOS has not enabled SME - * then don't advertise the feature (set in scattered.c). Also, - * since the SME support requires long mode, don't advertise the - * feature under CONFIG_X86_32. + * BIOS support is required for SME. If BIOS has enabled SME then + * adjust x86_phys_bits by the SME physical address space reduction + * value. If BIOS has not enabled SME then don't advertise the + * feature (set in scattered.c). Also, since the SME support requires + * long mode, don't advertise the feature under CONFIG_X86_32. */ if (cpu_has(c, X86_FEATURE_SME)) { - if (IS_ENABLED(CONFIG_X86_32)) { - clear_cpu_cap(c, X86_FEATURE_SME); - } else { - u64 msr; + u64 msr; - /* Check if SME is enabled */ - rdmsrl(MSR_K8_SYSCFG, msr); - if (!(msr & MSR_K8_SYSCFG_MEM_ENCRYPT)) + /* Check if SME is enabled */ + rdmsrl(MSR_K8_SYSCFG, msr); + if (msr & MSR_K8_SYSCFG_MEM_ENCRYPT) { + c->x86_phys_bits -= (cpuid_ebx(0x8000001f) >> 6) & 0x3f; + if (IS_ENABLED(CONFIG_X86_32)) clear_cpu_cap(c, X86_FEATURE_SME); + } else { + clear_cpu_cap(c, X86_FEATURE_SME); } } } -- 1.9.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org