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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DA5BEC4332F for ; Tue, 7 Dec 2021 09:52:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234527AbhLGJzv (ORCPT ); Tue, 7 Dec 2021 04:55:51 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35958 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234508AbhLGJzu (ORCPT ); Tue, 7 Dec 2021 04:55:50 -0500 Received: from mail-pj1-x1031.google.com (mail-pj1-x1031.google.com [IPv6:2607:f8b0:4864:20::1031]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1F1DBC061574; Tue, 7 Dec 2021 01:52:20 -0800 (PST) Received: by mail-pj1-x1031.google.com with SMTP id nh10-20020a17090b364a00b001a69adad5ebso2203019pjb.2; Tue, 07 Dec 2021 01:52:20 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=AggZV2m9pqXxnzeFQjDaBo+amTkLh6dgZ3TEXgFqWsI=; b=jPzFBXftZgwL/u/b+dpxrnveAEUhqe17Ub1F3EsLObND8KZPmoZXS+h1g9Ruq/Bu7L tLNRtcbwos5SL3ILogmtiGVDLuWmbYDovOQIj8h0KrecZB6XywdfJGzxuXp3cm49CntF Jk6rmlAslHbwZL0qGkEG8PzNtA4npiECpTZnseuLzas7/McE1/9518jyPxcUXpd0UBMn clWCY+dWgTHJqSHPRMvl+bpNLBoQcAgp1Rjic45gFMC2qrRgZUcTHyQzSXUZy+ylgAKR 8F/MufYIv8yDSndeqMx0hkkPivpVpNZNjnlg1zYd5gafOrb+DNYqW2tjdoCwZuguphN1 QCPA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=AggZV2m9pqXxnzeFQjDaBo+amTkLh6dgZ3TEXgFqWsI=; b=T0c5F5uw16KIHkwsHWeGxX32yfrRi4zqUi8ILGGMskDKERVbdd8+9buv6p5vMx80v7 HB393WCCnIbHH1Nk4KrO4FMvhdRS1Xdv+eMECzqI3keb9KCkZiStGcYQrH1vEwXulHDS EpHP2y5zQR99O6opGiEeccP3qkRVfHqqKDLbcssW8gq3MtszGMR3wW3WkmZO8IK9XQsE sm+8rtFhULXoizVYI8CzWiVUbfRKBj47+LNpOjsHVgkr6dty5Gp/ILUo7D/S+MqhG4HR xh8/dd9sK6sNFsegMAmtJDhaZ/M/ja5mZMCc6RxG5alFiLBwUbtVD3kNFla6zToWAJMi gX9g== X-Gm-Message-State: AOAM53087a1+L8A4+w/hR7G3kCl+oTXsDmdTVur/Xi7HQEl4pBxs8Qbn VWCOBtBfeYvH08kRA7AjHdBnhHXOT34= X-Google-Smtp-Source: ABdhPJwXzoP30B10NeSDpYRv0Zs/d3AIA+fHzA1z8/M0HJteC7Rk9UQ+4mEz3IzgEzEUPjf9d+EvWA== X-Received: by 2002:a17:903:2341:b0:142:1b63:98f3 with SMTP id c1-20020a170903234100b001421b6398f3mr49926698plh.49.1638870739547; Tue, 07 Dec 2021 01:52:19 -0800 (PST) Received: from localhost ([47.88.60.64]) by smtp.gmail.com with ESMTPSA id n3sm12377373pgc.76.2021.12.07.01.52.18 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 07 Dec 2021 01:52:19 -0800 (PST) From: Lai Jiangshan To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Paolo Bonzini Cc: Lai Jiangshan , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" Subject: [PATCH] KVM: X86: Raise #GP when clearing CR0_PG in 64 bit mode Date: Tue, 7 Dec 2021 17:52:30 +0800 Message-Id: <20211207095230.53437-1-jiangshanlai@gmail.com> X-Mailer: git-send-email 2.19.1.6.gb485710b MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Lai Jiangshan In the SDM: If the logical processor is in 64-bit mode or if CR4.PCIDE = 1, an attempt to clear CR0.PG causes a general-protection exception (#GP). Software should transition to compatibility mode and clear CR4.PCIDE before attempting to disable paging. Signed-off-by: Lai Jiangshan --- arch/x86/kvm/x86.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 00f5b2b82909..78c40ac3b197 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -906,7 +906,8 @@ int kvm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0) !load_pdptrs(vcpu, kvm_read_cr3(vcpu))) return 1; - if (!(cr0 & X86_CR0_PG) && kvm_read_cr4_bits(vcpu, X86_CR4_PCIDE)) + if (!(cr0 & X86_CR0_PG) && + (is_64_bit_mode(vcpu) || kvm_read_cr4_bits(vcpu, X86_CR4_PCIDE))) return 1; static_call(kvm_x86_set_cr0)(vcpu, cr0); -- 2.19.1.6.gb485710b