From patchwork Mon May 21 21:54:24 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= X-Patchwork-Id: 10416789 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 8AEEA6032B for ; Mon, 21 May 2018 21:54:39 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7B93128A72 for ; Mon, 21 May 2018 21:54:39 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7049D28AA8; Mon, 21 May 2018 21:54:39 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D614328A72 for ; Mon, 21 May 2018 21:54:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932070AbeEUVyg (ORCPT ); Mon, 21 May 2018 17:54:36 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:41450 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754251AbeEUVye (ORCPT ); Mon, 21 May 2018 17:54:34 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 6F7C340122A2; Mon, 21 May 2018 21:54:33 +0000 (UTC) Received: from t460.redhat.com (unknown [10.33.36.3]) by smtp.corp.redhat.com (Postfix) with ESMTP id 152B2215CDA7; Mon, 21 May 2018 21:54:31 +0000 (UTC) From: =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= To: qemu-devel@nongnu.org Cc: Konrad Rzeszutek Wilk , Richard Henderson , kvm@vger.kernel.org, Eduardo Habkost , Marcelo Tosatti , Paolo Bonzini , =?UTF-8?q?Daniel=20P=20=2E=20Berrang=C3=A9?= Subject: [PATCH 3/3] i386: Define the Virt SSBD MSR and handling of it (CVE-2018-3639) Date: Mon, 21 May 2018 22:54:24 +0100 Message-Id: <20180521215424.13520-4-berrange@redhat.com> In-Reply-To: <20180521215424.13520-1-berrange@redhat.com> References: <20180521215424.13520-1-berrange@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Mon, 21 May 2018 21:54:33 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Mon, 21 May 2018 21:54:33 +0000 (UTC) for IP:'10.11.54.6' DOMAIN:'int-mx06.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'berrange@redhat.com' RCPT:'' Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Konrad Rzeszutek Wilk "Some AMD processors only support a non-architectural means of enabling speculative store bypass disable (SSBD). To allow a simplified view of this to a guest, an architectural definition has been created through a new CPUID bit, 0x80000008_EBX[25], and a new MSR, 0xc001011f. With this, a hypervisor can virtualize the existence of this definition and provide an architectural method for using SSBD to a guest. Add the new CPUID feature, the new MSR and update the existing SSBD support to use this MSR when present." (from x86/speculation: Add virtualized speculative store bypass disable support in Linux). Signed-off-by: Konrad Rzeszutek Wilk Reviewed-by: Daniel P. Berrangé Signed-off-by: Daniel P. Berrangé --- target/i386/cpu.h | 2 ++ target/i386/kvm.c | 16 ++++++++++++++-- target/i386/machine.c | 20 ++++++++++++++++++++ 3 files changed, 36 insertions(+), 2 deletions(-) diff --git a/target/i386/cpu.h b/target/i386/cpu.h index f0b68905de..8ac13f6c2c 100644 --- a/target/i386/cpu.h +++ b/target/i386/cpu.h @@ -351,6 +351,7 @@ typedef enum X86Seg { #define MSR_IA32_FEATURE_CONTROL 0x0000003a #define MSR_TSC_ADJUST 0x0000003b #define MSR_IA32_SPEC_CTRL 0x48 +#define MSR_VIRT_SSBD 0xc001011f #define MSR_IA32_TSCDEADLINE 0x6e0 #define FEATURE_CONTROL_LOCKED (1<<0) @@ -1210,6 +1211,7 @@ typedef struct CPUX86State { uint32_t pkru; uint64_t spec_ctrl; + uint64_t virt_ssbd; /* End of state preserved by INIT (dummy marker). */ struct {} end_init_save; diff --git a/target/i386/kvm.c b/target/i386/kvm.c index d6666a4b19..0c656a91a4 100644 --- a/target/i386/kvm.c +++ b/target/i386/kvm.c @@ -93,6 +93,7 @@ static bool has_msr_hv_frequencies; static bool has_msr_hv_reenlightenment; static bool has_msr_xss; static bool has_msr_spec_ctrl; +static bool has_msr_virt_ssbd; static bool has_msr_smi_count; static uint32_t has_architectural_pmu_version; @@ -1233,6 +1234,9 @@ static int kvm_get_supported_msrs(KVMState *s) case MSR_IA32_SPEC_CTRL: has_msr_spec_ctrl = true; break; + case MSR_VIRT_SSBD: + has_msr_virt_ssbd = true; + break; } } } @@ -1721,6 +1725,10 @@ static int kvm_put_msrs(X86CPU *cpu, int level) if (has_msr_spec_ctrl) { kvm_msr_entry_add(cpu, MSR_IA32_SPEC_CTRL, env->spec_ctrl); } + if (has_msr_virt_ssbd) { + kvm_msr_entry_add(cpu, MSR_VIRT_SSBD, env->virt_ssbd); + } + #ifdef TARGET_X86_64 if (lm_capable_kernel) { kvm_msr_entry_add(cpu, MSR_CSTAR, env->cstar); @@ -2100,8 +2108,9 @@ static int kvm_get_msrs(X86CPU *cpu) if (has_msr_spec_ctrl) { kvm_msr_entry_add(cpu, MSR_IA32_SPEC_CTRL, 0); } - - + if (has_msr_virt_ssbd) { + kvm_msr_entry_add(cpu, MSR_VIRT_SSBD, 0); + } if (!env->tsc_valid) { kvm_msr_entry_add(cpu, MSR_IA32_TSC, 0); env->tsc_valid = !runstate_is_running(); @@ -2481,6 +2490,9 @@ static int kvm_get_msrs(X86CPU *cpu) case MSR_IA32_SPEC_CTRL: env->spec_ctrl = msrs[i].data; break; + case MSR_VIRT_SSBD: + env->virt_ssbd = msrs[i].data; + break; case MSR_IA32_RTIT_CTL: env->msr_rtit_ctrl = msrs[i].data; break; diff --git a/target/i386/machine.c b/target/i386/machine.c index fd99c0bbb4..4d98d367c1 100644 --- a/target/i386/machine.c +++ b/target/i386/machine.c @@ -916,6 +916,25 @@ static const VMStateDescription vmstate_msr_intel_pt = { } }; +static bool virt_ssbd_needed(void *opaque) +{ + X86CPU *cpu = opaque; + CPUX86State *env = &cpu->env; + + return env->virt_ssbd != 0; +} + +static const VMStateDescription vmstate_msr_virt_ssbd = { + .name = "cpu/virt_ssbd", + .version_id = 1, + .minimum_version_id = 1, + .needed = virt_ssbd_needed, + .fields = (VMStateField[]){ + VMSTATE_UINT64(env.virt_ssbd, X86CPU), + VMSTATE_END_OF_LIST() + } +}; + VMStateDescription vmstate_x86_cpu = { .name = "cpu", .version_id = 12, @@ -1039,6 +1058,7 @@ VMStateDescription vmstate_x86_cpu = { &vmstate_spec_ctrl, &vmstate_mcg_ext_ctl, &vmstate_msr_intel_pt, + &vmstate_msr_virt_ssbd, NULL } };