From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AG47ELvXW+ssCukrhmNFFM8QF3vPDUN2YEX81kOQe16Psl6ZuwJEYjkCEiM5M/UKBHfHShg4up3i ARC-Seal: i=1; a=rsa-sha256; t=1520641378; cv=none; d=google.com; s=arc-20160816; b=vSy1oHViVU4Z7fljxUc6xbKtfp4Grb77m1KDPOsIB1tWwuts3t/GiRikSs8tagb9GA tB2mNc5fvm+UXy9xp9etWVGTFwTQOfi7yjMH2Z7gH3Wanl06FkwGeyv6ja7fWLdWetWf wWGAlX3PI4kazUP6j1r9sVPUXbc0oS3RvTcpadAfqavDz34thP7fVZHAyKlmvVqvhluo qZXil94MgHAF99Zd1QIwmu8XpUavSYxaK54ILXAn8tQIoVNYUacokrPYBfe/13heP3y0 FYoXuk66cghyYutw1ILhAwKxSqZTeXeUhaP6gCP+MOSel9wY0c3G7f2zsdRVN9Vi/00T LM3g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=qock6rUIyhZVeXDSVq0yELL4IxqG6H54MOypZxMWRo0=; b=zfNBar86gRsiPPi8BzkfSUqzCTdEnwX1lAa6sX4oVwkp0k1pA8aofkXMK76AqiNHOv eDxBzTWeFt0eYWxMiWB5ztkmRQb/7SdNwGBvFs9lrJQKSkQgocVxG5pMXRuFdCWOLI9D NQSgWQ/ls5LOOGe2qKXpHvAZwABtqpnmWVk63CMW/rB0P39gkHXpCGUee9TwoK4zmmOa hW7jh+hwn7G2wH+DhHwO6Vt80WYUx7q+yzo3uFOEWjXhXUgyu7izZJ5SDjyeD+6uUMnu 1z0e9AEr231w7K3kahmpce6Au5ob21I1oBnNKSCHW0OOWQUxjiSj2p+atrIX/DPn8gF7 UuXw== ARC-Authentication-Results: i=1; mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 185.236.200.248 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org Authentication-Results: mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 185.236.200.248 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Paolo Bonzini , Jim Mattson , David Woodhouse , KarimAllah Ahmed , Linus Torvalds , Peter Zijlstra , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Thomas Gleixner , kvm@vger.kernel.org, Ingo Molnar Subject: [PATCH 4.9 22/65] KVM/x86: Remove indirect MSR op calls from SPEC_CTRL Date: Fri, 9 Mar 2018 16:18:22 -0800 Message-Id: <20180310001826.702902379@linuxfoundation.org> X-Mailer: git-send-email 2.16.2 In-Reply-To: <20180310001824.927996722@linuxfoundation.org> References: <20180310001824.927996722@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1594508053489211194?= X-GMAIL-MSGID: =?utf-8?q?1594508053489211194?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Paolo Bonzini commit ecb586bd29c99fb4de599dec388658e74388daad upstream. Having a paravirt indirect call in the IBRS restore path is not a good idea, since we are trying to protect from speculative execution of bogus indirect branch targets. It is also slower, so use native_wrmsrl() on the vmentry path too. Signed-off-by: Paolo Bonzini Reviewed-by: Jim Mattson Cc: David Woodhouse Cc: KarimAllah Ahmed Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Radim Krčmář Cc: Thomas Gleixner Cc: kvm@vger.kernel.org Cc: stable@vger.kernel.org Fixes: d28b387fb74da95d69d2615732f50cceb38e9a4d Link: http://lkml.kernel.org/r/20180222154318.20361-2-pbonzini@redhat.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/svm.c | 7 ++++--- arch/x86/kvm/vmx.c | 7 ++++--- 2 files changed, 8 insertions(+), 6 deletions(-) --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -44,6 +44,7 @@ #include #include #include +#include #include #include @@ -4919,7 +4920,7 @@ static void svm_vcpu_run(struct kvm_vcpu * being speculatively taken. */ if (svm->spec_ctrl) - wrmsrl(MSR_IA32_SPEC_CTRL, svm->spec_ctrl); + native_wrmsrl(MSR_IA32_SPEC_CTRL, svm->spec_ctrl); asm volatile ( "push %%" _ASM_BP "; \n\t" @@ -5029,10 +5030,10 @@ static void svm_vcpu_run(struct kvm_vcpu * save it. */ if (!msr_write_intercepted(vcpu, MSR_IA32_SPEC_CTRL)) - rdmsrl(MSR_IA32_SPEC_CTRL, svm->spec_ctrl); + svm->spec_ctrl = native_read_msr(MSR_IA32_SPEC_CTRL); if (svm->spec_ctrl) - wrmsrl(MSR_IA32_SPEC_CTRL, 0); + native_wrmsrl(MSR_IA32_SPEC_CTRL, 0); /* Eliminate branch target predictions from guest mode */ vmexit_fill_RSB(); --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -49,6 +49,7 @@ #include #include #include +#include #include #include "trace.h" @@ -8906,7 +8907,7 @@ static void __noclone vmx_vcpu_run(struc * being speculatively taken. */ if (vmx->spec_ctrl) - wrmsrl(MSR_IA32_SPEC_CTRL, vmx->spec_ctrl); + native_wrmsrl(MSR_IA32_SPEC_CTRL, vmx->spec_ctrl); vmx->__launched = vmx->loaded_vmcs->launched; asm( @@ -9042,10 +9043,10 @@ static void __noclone vmx_vcpu_run(struc * save it. */ if (!msr_write_intercepted(vcpu, MSR_IA32_SPEC_CTRL)) - rdmsrl(MSR_IA32_SPEC_CTRL, vmx->spec_ctrl); + vmx->spec_ctrl = native_read_msr(MSR_IA32_SPEC_CTRL); if (vmx->spec_ctrl) - wrmsrl(MSR_IA32_SPEC_CTRL, 0); + native_wrmsrl(MSR_IA32_SPEC_CTRL, 0); /* Eliminate branch target predictions from guest mode */ vmexit_fill_RSB();