From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9DCC2C49ED7 for ; Fri, 13 Sep 2019 13:29:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 770F420640 for ; Fri, 13 Sep 2019 13:29:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1568381393; bh=XVYIv0Ox5JA7Fj2C5eqS00irDiXQLvRnc/N5P47Pxok=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=rBwt27YHB8mwQG8t37nWWibuG2HO/RTC3DwF5NXvwM1geVEe6fIsh0gLoIFmAFbp7 aK7jLZgwatjJ2LsXZ4BtO7/5wHQi7lzXm3t1BUjf0dSE2Y6o7H9UQFR7QNlSnpkzYU hxyXVEOmACYsmvhbca04F0k6/VYw2Vmdao50/5TY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389314AbfIMNSi (ORCPT ); Fri, 13 Sep 2019 09:18:38 -0400 Received: from mail.kernel.org ([198.145.29.99]:46198 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389668AbfIMNSh (ORCPT ); Fri, 13 Sep 2019 09:18:37 -0400 Received: from localhost (unknown [104.132.45.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id F3EE4206A5; Fri, 13 Sep 2019 13:18:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1568380715; bh=XVYIv0Ox5JA7Fj2C5eqS00irDiXQLvRnc/N5P47Pxok=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hd6kEE2AuBEJwhZvWY0xVc8C7mATJCwtMGH4Se2h2BqLQdYz6RnbGVWuvaJc6rqqF tgbK5Z47t/8K9zi+Oj4jFY1RV3wGuNgUqP3KpI33G/YZIxF7gPqsaHxTDwpLyUR+Az 60xpKYGNFs4pwBQMnvLDCktB8x4O5YPxvvRzEVlI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sean Christopherson , Jim Mattson , Paolo Bonzini , Sasha Levin Subject: [PATCH 4.19 154/190] KVM: VMX: Fix handling of #MC that occurs during VM-Entry Date: Fri, 13 Sep 2019 14:06:49 +0100 Message-Id: <20190913130612.227146438@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190913130559.669563815@linuxfoundation.org> References: <20190913130559.669563815@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org [ Upstream commit beb8d93b3e423043e079ef3dda19dad7b28467a8 ] A previous fix to prevent KVM from consuming stale VMCS state after a failed VM-Entry inadvertantly blocked KVM's handling of machine checks that occur during VM-Entry. Per Intel's SDM, a #MC during VM-Entry is handled in one of three ways, depending on when the #MC is recognoized. As it pertains to this bug fix, the third case explicitly states EXIT_REASON_MCE_DURING_VMENTRY is handled like any other VM-Exit during VM-Entry, i.e. sets bit 31 to indicate the VM-Entry failed. If a machine-check event occurs during a VM entry, one of the following occurs: - The machine-check event is handled as if it occurred before the VM entry: ... - The machine-check event is handled after VM entry completes: ... - A VM-entry failure occurs as described in Section 26.7. The basic exit reason is 41, for "VM-entry failure due to machine-check event". Explicitly handle EXIT_REASON_MCE_DURING_VMENTRY as a one-off case in vmx_vcpu_run() instead of binning it into vmx_complete_atomic_exit(). Doing so allows vmx_vcpu_run() to handle VMX_EXIT_REASONS_FAILED_VMENTRY in a sane fashion and also simplifies vmx_complete_atomic_exit() since VMCS.VM_EXIT_INTR_INFO is guaranteed to be fresh. Fixes: b060ca3b2e9e7 ("kvm: vmx: Handle VMLAUNCH/VMRESUME failure properly") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson Reviewed-by: Jim Mattson Signed-off-by: Paolo Bonzini Signed-off-by: Sasha Levin --- arch/x86/kvm/vmx.c | 20 ++++++++------------ 1 file changed, 8 insertions(+), 12 deletions(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index e4bba840a0708..82253d31842a2 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -10438,28 +10438,21 @@ static void vmx_apicv_post_state_restore(struct kvm_vcpu *vcpu) static void vmx_complete_atomic_exit(struct vcpu_vmx *vmx) { - u32 exit_intr_info = 0; - u16 basic_exit_reason = (u16)vmx->exit_reason; - - if (!(basic_exit_reason == EXIT_REASON_MCE_DURING_VMENTRY - || basic_exit_reason == EXIT_REASON_EXCEPTION_NMI)) + if (vmx->exit_reason != EXIT_REASON_EXCEPTION_NMI) return; - if (!(vmx->exit_reason & VMX_EXIT_REASONS_FAILED_VMENTRY)) - exit_intr_info = vmcs_read32(VM_EXIT_INTR_INFO); - vmx->exit_intr_info = exit_intr_info; + vmx->exit_intr_info = vmcs_read32(VM_EXIT_INTR_INFO); /* if exit due to PF check for async PF */ - if (is_page_fault(exit_intr_info)) + if (is_page_fault(vmx->exit_intr_info)) vmx->vcpu.arch.apf.host_apf_reason = kvm_read_and_reset_pf_reason(); /* Handle machine checks before interrupts are enabled */ - if (basic_exit_reason == EXIT_REASON_MCE_DURING_VMENTRY || - is_machine_check(exit_intr_info)) + if (is_machine_check(vmx->exit_intr_info)) kvm_machine_check(); /* We need to handle NMIs before interrupts are enabled */ - if (is_nmi(exit_intr_info)) { + if (is_nmi(vmx->exit_intr_info)) { kvm_before_interrupt(&vmx->vcpu); asm("int $2"); kvm_after_interrupt(&vmx->vcpu); @@ -10980,6 +10973,9 @@ static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu) vmx->idt_vectoring_info = 0; vmx->exit_reason = vmx->fail ? 0xdead : vmcs_read32(VM_EXIT_REASON); + if ((u16)vmx->exit_reason == EXIT_REASON_MCE_DURING_VMENTRY) + kvm_machine_check(); + if (vmx->fail || (vmx->exit_reason & VMX_EXIT_REASONS_FAILED_VMENTRY)) return; -- 2.20.1