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 97175C4167B for ; Fri, 30 Dec 2022 16:25:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235229AbiL3QZD (ORCPT ); Fri, 30 Dec 2022 11:25:03 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43462 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229967AbiL3QZB (ORCPT ); Fri, 30 Dec 2022 11:25:01 -0500 Received: from mail-pg1-x549.google.com (mail-pg1-x549.google.com [IPv6:2607:f8b0:4864:20::549]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D820163FC for ; Fri, 30 Dec 2022 08:25:00 -0800 (PST) Received: by mail-pg1-x549.google.com with SMTP id s76-20020a632c4f000000b0049ceb0f185eso3231515pgs.7 for ; Fri, 30 Dec 2022 08:25:00 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=MpDOjh28JsAURpTnDCHBXTn8SRkFcmuZMnLUukHdgGY=; b=HGyFmKbPz7YAmNGmGmlYBVFZWnojZVPDD4tYUvlWgQ5Ks3HZ1/ODD0SZJQsr+6Gr4D LrY5sn2QSd4PIXvXXZF1r7EwNFRKZ31PG+oaZwljCYCmxJCWXVWJjqtnTXVQBxAS7qsg haEzrdiR7SF2eU0+mMTsExEjBX3bnHWz1qbBna0ScTDg6Dn2DENgreS0ttev/SWcnNe/ xP1q+ySlSnYGt5hOFiGjLejCjNb64P8gmJC8m+5J85Fai33M7d/j/ivnX763D6cNUHlk PwWR1asefPZMbEpwRj9Z2PENxeRc9v0PZ6Ok9umhZ5dOjaES1MgW435GZZicFOIY0tdJ hndw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=MpDOjh28JsAURpTnDCHBXTn8SRkFcmuZMnLUukHdgGY=; b=kUVsF62VJpsUzWeoghv/6w/Gs3/jpOVOxge+Y7uc3xTW9X/oYwbhJbLgnWlVqyy9Mr YybtHptiCvfgK0StcAypgZyPPgm1kp23T0WEYkLw3VFb8xSJeN8j834awdoDv1P5pTFu qlZJRlrK7iOyyVdvzZArtjwey5Kene7p3S1jasdJQha7mzOQV/KMNeYt/AqKMJTZBs6P wLheBYZZxSXUbHH67ud1Nk+R2MXo/BtGIR+47oHVXp/mPKP9QW5mTuzFmIYKbfeMiMFn Nl+dJXb0Jp9CYqsqd8b2fR5MD5xXNbEX/15chq4/6U/9yaJJW0MTKLi1K2UVB/+DOI08 LYDw== X-Gm-Message-State: AFqh2ko1hPmICGh9Hx2E30v/ktNdKryvvKp1aynURy4U52NEmiBl3R/l dgC1X3bex5sRGZDMogfd5Ng3XM2iyRB6ihAwl0GzzVRiK/66gMdNat2aMinlKiDGvnDPF2DYwMX WMsBUpsgv1Hjk0tZ6YWzU6wVrizY15ZkS7Zq4N1sSuOoAI5pva28Fkfj9AQF4KO6YQZzw X-Google-Smtp-Source: AMrXdXsDV2jrkutrIIZQu2b6XbKlj80oZd7VAJGoSGgCQIwewPK6P+k7/c1jS1+TUG2V+DPEhEaSjrYWSEPD0DLO X-Received: from aaronlewis.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:2675]) (user=aaronlewis job=sendgmr) by 2002:a17:903:2653:b0:189:cdc8:7261 with SMTP id je19-20020a170903265300b00189cdc87261mr2140432plb.168.1672417500198; Fri, 30 Dec 2022 08:25:00 -0800 (PST) Date: Fri, 30 Dec 2022 16:24:37 +0000 In-Reply-To: <20221230162442.3781098-1-aaronlewis@google.com> Mime-Version: 1.0 References: <20221230162442.3781098-1-aaronlewis@google.com> X-Mailer: git-send-email 2.39.0.314.g84b9a713c41-goog Message-ID: <20221230162442.3781098-2-aaronlewis@google.com> Subject: [PATCH v2 1/6] KVM: x86: Clear all supported MPX xfeatures if they are not all set From: Aaron Lewis To: kvm@vger.kernel.org Cc: pbonzini@redhat.com, jmattson@google.com, seanjc@google.com, Aaron Lewis Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Be a good citizen and don't allow any of the supported MPX xfeatures[1] to be set if they can't all be set. That way userspace or a guest doesn't fail if it attempts to set them in XCR0. [1] CPUID.(EAX=0DH,ECX=0):EAX.BNDREGS[bit-3] CPUID.(EAX=0DH,ECX=0):EAX.BNDCSR[bit-4] Suggested-by: Jim Mattson Signed-off-by: Aaron Lewis --- arch/x86/kvm/cpuid.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index c4e8257629165..2431c46d456b4 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -855,6 +855,16 @@ static int __do_cpuid_func_emulated(struct kvm_cpuid_array *array, u32 func) return 0; } +static u64 sanitize_xcr0(u64 xcr0) +{ + u64 mask; + + mask = XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR; + if ((xcr0 & mask) != mask) + xcr0 &= ~mask; + + return xcr0; +} + static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function) { struct kvm_cpuid_entry2 *entry; @@ -982,6 +992,8 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function) u64 permitted_xcr0 = kvm_caps.supported_xcr0 & xstate_get_guest_group_perm(); u64 permitted_xss = kvm_caps.supported_xss; + permitted_xcr0 = sanitize_xcr0(permitted_xcr0); + entry->eax &= permitted_xcr0; entry->ebx = xstate_required_size(permitted_xcr0, false); entry->ecx = entry->ebx; -- 2.39.0.314.g84b9a713c41-goog