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=-26.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 26B85C433F5 for ; Tue, 21 Sep 2021 02:10:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0BB2061177 for ; Tue, 21 Sep 2021 02:10:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245384AbhIUCKY (ORCPT ); Mon, 20 Sep 2021 22:10:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34582 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238081AbhIUB5E (ORCPT ); Mon, 20 Sep 2021 21:57:04 -0400 Received: from mail-qt1-x84a.google.com (mail-qt1-x84a.google.com [IPv6:2607:f8b0:4864:20::84a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 74EAFC06B671 for ; Mon, 20 Sep 2021 17:03:15 -0700 (PDT) Received: by mail-qt1-x84a.google.com with SMTP id r5-20020ac85e85000000b0029bd6ee5179so197796443qtx.18 for ; Mon, 20 Sep 2021 17:03:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=reply-to:date:in-reply-to:message-id:mime-version:references :subject:from:to:cc; bh=TaOFnh9pXKvlFAgxCXG8pz2yPTn2EvG+MXmMc1YbXv8=; b=XANYy4kQA/dxnSdwpOjKZufPVeEHBPsLJR8SQwiKtMc/hrrjoE7YTGFtL8MtYJjzkT TpYG7RtwfHAcomNdxfIF7ecGtQZ4DOxCFVk1woATwZHhrJKx5O6emgjxNwblBdxfE8ms Qpss2GgcvkyBWXNIyQNnNlUEY1GGfmd2r3usj31xYg6GmBvUNLBEWY+Jq+HWQDOc6J3k 5XtL7dVMZHHKoCt0nnpNLCnh2cahVJfhWeAY60+hwmOW2eOTMEvoPb3YFTqSNqPCRuIL PWobg/OwORqfRog2zuhRdv2acJCAICDWYwqN3ANTcGt++s3JAAAibPprfkcwBQNESkJQ wcIw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:reply-to:date:in-reply-to:message-id :mime-version:references:subject:from:to:cc; bh=TaOFnh9pXKvlFAgxCXG8pz2yPTn2EvG+MXmMc1YbXv8=; b=PUNEzqFcz6JSioVNdsJlRMTt41rvwXjC3brkWQ06QK2qCZIfVIqDYdB/SWifAP7XqZ sEysctlBavQK2O2IJWxCFxQTozUKiz9syBnIvpI0N+0XN59ze+xdKtwUNE2BMP39EPBu X2Se+2r9NoySGYNExg503ceRaLPeWTGTnHjdPC3VuUCmgZ/33LWJgO6Ms5BzrOcbOqJO jOkdKMuSOFof/Sbp3z7IowLdF5MxBiGGUbLJ7CTyAVQissxOQZC60b6sFkdH+cM3iaSp cSDB8snOuH36a9Xkm5Ua7o3DO2QSZK4nDE2pwkmGcxdMXouLAmF9rqYFg+8TnCr2lEPT toug== X-Gm-Message-State: AOAM532xR1U0B4Qp8fjgQwLIzbtdrV+qPEG5rjcRMQuf0m58+er/qjAA EMBjpBHusTyvmDQLHIt8g1h/MjlWy4o= X-Google-Smtp-Source: ABdhPJxGRjzoPJfx96khcwuanlK/hcJNUg9koX7RsTp6tA76rmSNFpnq0dcsSmvKzzEtOotVi88bp//wcH0= X-Received: from seanjc798194.pdx.corp.google.com ([2620:15c:90:200:e430:8766:b902:5ee3]) (user=seanjc job=sendgmr) by 2002:ad4:4741:: with SMTP id c1mr14047272qvx.7.1632182594679; Mon, 20 Sep 2021 17:03:14 -0700 (PDT) Reply-To: Sean Christopherson Date: Mon, 20 Sep 2021 17:02:57 -0700 In-Reply-To: <20210921000303.400537-1-seanjc@google.com> Message-Id: <20210921000303.400537-5-seanjc@google.com> Mime-Version: 1.0 References: <20210921000303.400537-1-seanjc@google.com> X-Mailer: git-send-email 2.33.0.464.g1972c5931b-goog Subject: [PATCH v2 04/10] KVM: x86: Remove defunct setting of CR0.ET for guests during vCPU create From: Sean Christopherson To: Paolo Bonzini Cc: Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Reiji Watanabe Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Drop code to set CR0.ET for the guest during initialization of the guest FPU. The code was added as a misguided bug fix by commit 380102c8e431 ("KVM Set the ET flag in CR0 after initializing FX") to resolve an issue where vcpu->cr0 (now vcpu->arch.cr0) was not correctly initialized on SVM systems. While init_vmcb() did set CR0.ET, it only did so in the VMCB, and subtly did not update vcpu->cr0. Stuffing CR0.ET worked around the immediate problem, but did not fix the real bug of vcpu->cr0 and the VMCB being out of sync. That underlying bug was eventually remedied by commit 18fa000ae453 ("KVM: SVM: Reset cr0 properly on vcpu reset"). No functional change intended. Signed-off-by: Sean Christopherson --- arch/x86/kvm/x86.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index ab907a0b9eeb..e0bff5473813 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -10628,8 +10628,6 @@ static void fx_init(struct kvm_vcpu *vcpu) * Ensure guest xcr0 is valid for loading */ vcpu->arch.xcr0 = XFEATURE_MASK_FP; - - vcpu->arch.cr0 |= X86_CR0_ET; } void kvm_free_guest_fpu(struct kvm_vcpu *vcpu) -- 2.33.0.464.g1972c5931b-goog