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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 9F8CAC47404 for ; Wed, 9 Oct 2019 17:31:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7B5BF21848 for ; Wed, 9 Oct 2019 17:31:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570642285; bh=koP+fiLIJDAGVLtJBIFR6XpLcdV7DAt7U4NKHtXTogc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=usqWD5zF0KhGadlbv2WUmE/uGY45tlqKX7VVudnfQutaYdi4UoCVl4RCjWyZ2PoLq zs9ippmfW2MXbCbqcbs+w9CkjEBdCot5UH218e5tMJfgc42OnPU3CjeTM5dQAUZzlf SQzig84NlLfc4yKdviUJ7LfyMujz0pfNRd/0z7jw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732929AbfJIRbY (ORCPT ); Wed, 9 Oct 2019 13:31:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:48298 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732076AbfJIRYB (ORCPT ); Wed, 9 Oct 2019 13:24:01 -0400 Received: from sasha-vm.mshome.net (unknown [167.220.2.234]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 972A7222D3; Wed, 9 Oct 2019 17:24:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570641840; bh=koP+fiLIJDAGVLtJBIFR6XpLcdV7DAt7U4NKHtXTogc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fS9QeA0qTFxuNaffxfh5qnj17B//3pg5mpOjEcf+IJ0BxDJjEm3pTttdfyYhnr6lo fa4p7Bur1ebkBMYrVqzeIbWh3ehjI46tUgO3DVzRASB3SSNUkqTOU6xwaAanuqhcZK MUW20b1xrTwJeo53cnRqG2SmETBDVe7FCnuvb8l8= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Jim Mattson , Marc Orr , Peter Shier , Jacob Xu , Sean Christopherson , Paolo Bonzini , Sasha Levin , kvm@vger.kernel.org Subject: [PATCH AUTOSEL 5.3 26/68] kvm: x86: Improve emulation of CPUID leaves 0BH and 1FH Date: Wed, 9 Oct 2019 13:05:05 -0400 Message-Id: <20191009170547.32204-26-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191009170547.32204-1-sashal@kernel.org> References: <20191009170547.32204-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jim Mattson [ Upstream commit 43561123ab3759eb6ff47693aec1a307af0aef83 ] For these CPUID leaves, the EDX output is not dependent on the ECX input (i.e. the SIGNIFCANT_INDEX flag doesn't apply to EDX). Furthermore, the low byte of the ECX output is always identical to the low byte of the ECX input. KVM does not produce the correct ECX and EDX outputs for any undefined subleaves beyond the first. Special-case these CPUID leaves in kvm_cpuid, so that the ECX and EDX outputs are properly generated for all undefined subleaves. Fixes: 0771671749b59a ("KVM: Enhance guest cpuid management") Fixes: a87f2d3a6eadab ("KVM: x86: Add Intel CPUID.1F cpuid emulation support") Signed-off-by: Jim Mattson Reviewed-by: Marc Orr Reviewed-by: Peter Shier Reviewed-by: Jacob Xu Cc: Sean Christopherson Cc: Paolo Bonzini Signed-off-by: Paolo Bonzini Signed-off-by: Sasha Levin --- arch/x86/kvm/cpuid.c | 83 +++++++++++++++++++++++++------------------- 1 file changed, 47 insertions(+), 36 deletions(-) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 429648ae5653f..a8a46e0b3d13b 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -962,53 +962,64 @@ struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu, EXPORT_SYMBOL_GPL(kvm_find_cpuid_entry); /* - * If no match is found, check whether we exceed the vCPU's limit - * and return the content of the highest valid _standard_ leaf instead. - * This is to satisfy the CPUID specification. + * If the basic or extended CPUID leaf requested is higher than the + * maximum supported basic or extended leaf, respectively, then it is + * out of range. */ -static struct kvm_cpuid_entry2* check_cpuid_limit(struct kvm_vcpu *vcpu, - u32 function, u32 index) +static bool cpuid_function_in_range(struct kvm_vcpu *vcpu, u32 function) { - struct kvm_cpuid_entry2 *maxlevel; - - maxlevel = kvm_find_cpuid_entry(vcpu, function & 0x80000000, 0); - if (!maxlevel || maxlevel->eax >= function) - return NULL; - if (function & 0x80000000) { - maxlevel = kvm_find_cpuid_entry(vcpu, 0, 0); - if (!maxlevel) - return NULL; - } - return kvm_find_cpuid_entry(vcpu, maxlevel->eax, index); + struct kvm_cpuid_entry2 *max; + + max = kvm_find_cpuid_entry(vcpu, function & 0x80000000, 0); + return max && function <= max->eax; } bool kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx, bool check_limit) { u32 function = *eax, index = *ecx; - struct kvm_cpuid_entry2 *best; - bool entry_found = true; - - best = kvm_find_cpuid_entry(vcpu, function, index); - - if (!best) { - entry_found = false; - if (!check_limit) - goto out; + struct kvm_cpuid_entry2 *entry; + struct kvm_cpuid_entry2 *max; + bool found; - best = check_cpuid_limit(vcpu, function, index); + entry = kvm_find_cpuid_entry(vcpu, function, index); + found = entry; + /* + * Intel CPUID semantics treats any query for an out-of-range + * leaf as if the highest basic leaf (i.e. CPUID.0H:EAX) were + * requested. + */ + if (!entry && check_limit && !cpuid_function_in_range(vcpu, function)) { + max = kvm_find_cpuid_entry(vcpu, 0, 0); + if (max) { + function = max->eax; + entry = kvm_find_cpuid_entry(vcpu, function, index); + } } - -out: - if (best) { - *eax = best->eax; - *ebx = best->ebx; - *ecx = best->ecx; - *edx = best->edx; - } else + if (entry) { + *eax = entry->eax; + *ebx = entry->ebx; + *ecx = entry->ecx; + *edx = entry->edx; + } else { *eax = *ebx = *ecx = *edx = 0; - trace_kvm_cpuid(function, *eax, *ebx, *ecx, *edx, entry_found); - return entry_found; + /* + * When leaf 0BH or 1FH is defined, CL is pass-through + * and EDX is always the x2APIC ID, even for undefined + * subleaves. Index 1 will exist iff the leaf is + * implemented, so we pass through CL iff leaf 1 + * exists. EDX can be copied from any existing index. + */ + if (function == 0xb || function == 0x1f) { + entry = kvm_find_cpuid_entry(vcpu, function, 1); + if (entry) { + *ecx = index & 0xff; + *edx = entry->edx; + } + } + } + trace_kvm_cpuid(function, *eax, *ebx, *ecx, *edx, found); + return found; } EXPORT_SYMBOL_GPL(kvm_cpuid); -- 2.20.1