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=-7.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS autolearn=ham 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 662B5C10F03 for ; Fri, 22 Mar 2019 10:02:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 32DE02070D for ; Fri, 22 Mar 2019 10:02:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553248925; bh=K8WWbUPcZEQMVKF2d5s6TMLTxfAb4VOxxvm2gWpUQ9s=; h=Subject:To:Cc:From:Date:List-ID:From; b=Q77v8ri6KwzX7BEzDO+MJMJqOXfXiiNQPyvugpBU0/NSnHkIt0JkEXsXYALFhufEr 1M9D/+V9NrX6Dob3Xq0NBQV00dCMq+9A/RipsF1tbZGafQLSH8s4mztNV9vKvI/w34 bjHdY7uCP1J9kEMwpafNiaLSfXmCwIx9kJhiBHlA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727967AbfCVKCE (ORCPT ); Fri, 22 Mar 2019 06:02:04 -0400 Received: from wout1-smtp.messagingengine.com ([64.147.123.24]:33081 "EHLO wout1-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727952AbfCVKCE (ORCPT ); Fri, 22 Mar 2019 06:02:04 -0400 Received: from compute6.internal (compute6.nyi.internal [10.202.2.46]) by mailout.west.internal (Postfix) with ESMTP id 395A846D2; Fri, 22 Mar 2019 06:02:03 -0400 (EDT) Received: from mailfrontend1 ([10.202.2.162]) by compute6.internal (MEProxy); Fri, 22 Mar 2019 06:02:03 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:content-type :date:from:message-id:mime-version:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm2; bh=pXTEg2 5xdgJhqkThiyaKaGBfddD467nwEHPxIgwJRVQ=; b=O+esE5Lw4TJJEwGw4C62AW dLp1dQaLijpltsjrj7Pq6EFE9+iUA+dtyoNSFyqtt3+wYrbM9N43eiy3xrYH1Iwz 7eDL//zzralJ5ALsVd8wLk7xaK2G5E56W0GnFcqwbQZwkdY64ML94NUG9FWEYh0U gix2mfJRC7kyTPoIN4cCcdKeKLUvfEHIBgnIdL7ifKSmsw8ptzLopNc2mR1Cb5Ea nmSlwdgSMpgTlPqPYMi/+qWGpgABvJOOpG1Bs/t3jemVHYLlnC80lGMK830v7Lh0 AcPTJA3F4Lg5m6OFu+tLgpXu2x4o8JQXUr/UA48O9eRlqWX+cYXI+gaq4irE6x5g == X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedutddrjedugddtlecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecunecujfgurhepuffvhfffkfggtgfgsehtkeertddttd flnecuhfhrohhmpeeoghhrvghgkhhhsehlihhnuhigfhhouhhnuggrthhiohhnrdhorhhg qeenucffohhmrghinhepghhnuhdrohhrghenucfkphepkeefrdekiedrkeelrddutdejne curfgrrhgrmhepmhgrihhlfhhrohhmpehgrhgvgheskhhrohgrhhdrtghomhenucevlhhu shhtvghrufhiiigvpedu X-ME-Proxy: Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) by mail.messagingengine.com (Postfix) with ESMTPA id 1E6BDE44D7; Fri, 22 Mar 2019 06:02:02 -0400 (EDT) Subject: FAILED: patch "[PATCH] KVM: VMX: Compare only a single byte for VMCS' "launched" in" failed to apply to 4.4-stable tree To: sean.j.christopherson@intel.com, jmattson@google.com, konrad.wilk@oracle.com, pbonzini@redhat.com, stable@vger.kernel.org Cc: From: Date: Fri, 22 Mar 2019 11:01:56 +0100 Message-ID: <155324891660212@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 61c08aa9606d4e48a8a50639c956448a720174c3 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Fri, 25 Jan 2019 07:40:48 -0800 Subject: [PATCH] KVM: VMX: Compare only a single byte for VMCS' "launched" in vCPU-run The vCPU-run asm blob does a manual comparison of a VMCS' launched status to execute the correct VM-Enter instruction, i.e. VMLAUNCH vs. VMRESUME. The launched flag is a bool, which is a typedef of _Bool. C99 does not define an exact size for _Bool, stating only that is must be large enough to hold '0' and '1'. Most, if not all, compilers use a single byte for _Bool, including gcc[1]. Originally, 'launched' was of type 'int' and so the asm blob used 'cmpl' to check the launch status. When 'launched' was moved to be stored on a per-VMCS basis, struct vcpu_vmx's "temporary" __launched flag was added in order to avoid having to pass the current VMCS into the asm blob. The new '__launched' was defined as a 'bool' and not an 'int', but the 'cmp' instruction was not updated. This has not caused any known problems, likely due to compilers aligning variables to 4-byte or 8-byte boundaries and KVM zeroing out struct vcpu_vmx during allocation. I.e. vCPU-run accesses "junk" data, it just happens to always be zero and so doesn't affect the result. [1] https://gcc.gnu.org/ml/gcc-patches/2000-10/msg01127.html Fixes: d462b8192368 ("KVM: VMX: Keep list of loaded VMCSs, instead of vcpus") Cc: Reviewed-by: Jim Mattson Reviewed-by: Konrad Rzeszutek Wilk Signed-off-by: Sean Christopherson Signed-off-by: Paolo Bonzini diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 95d618045001..fdb6305cc971 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -6402,7 +6402,7 @@ static void __vmx_vcpu_run(struct kvm_vcpu *vcpu, struct vcpu_vmx *vmx) "mov %%" _ASM_AX", %%cr2 \n\t" "3: \n\t" /* Check if vmlaunch or vmresume is needed */ - "cmpl $0, %c[launched](%%" _ASM_CX ") \n\t" + "cmpb $0, %c[launched](%%" _ASM_CX ") \n\t" /* Load guest registers. Don't clobber flags. */ "mov %c[rax](%%" _ASM_CX "), %%" _ASM_AX " \n\t" "mov %c[rbx](%%" _ASM_CX "), %%" _ASM_BX " \n\t"