From patchwork Mon May 17 14:03:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 440562 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=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, 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 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 E3BD7C433B4 for ; Mon, 17 May 2021 15:47:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C1C2B61057 for ; Mon, 17 May 2021 15:47:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245557AbhEQPsw (ORCPT ); Mon, 17 May 2021 11:48:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:36524 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244617AbhEQPqu (ORCPT ); Mon, 17 May 2021 11:46:50 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3735B61D3A; Mon, 17 May 2021 14:44:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1621262674; bh=rvO3SlW0XpyOs4ayDRzP2T/+tAG9p/YataboeAOhmwc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=F58xz+1j/nQCcGG5mLVSVRlp9ZjsAJm2q95deMF3MKvC9CzlJ+4xJcfmPtaNLAhzM 7q3B9PGcuzNtoWolz98GsIautwoTvkf8GSIILGe/AUJyr7cU/trHc8MoVcI9WBF5iJ k72TLby6rg7Y78911aF+iQ0CGbS5W9V4oOq5zEfY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sean Christopherson , Jim Mattson , Reiji Watanabe , Paolo Bonzini Subject: [PATCH 5.10 256/289] KVM: x86: Emulate RDPID only if RDTSCP is supported Date: Mon, 17 May 2021 16:03:01 +0200 Message-Id: <20210517140313.762996034@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210517140305.140529752@linuxfoundation.org> References: <20210517140305.140529752@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Sean Christopherson commit 85d0011264da24be08ae907d7f29983a597ca9b1 upstream. Do not advertise emulation support for RDPID if RDTSCP is unsupported. RDPID emulation subtly relies on MSR_TSC_AUX to exist in hardware, as both vmx_get_msr() and svm_get_msr() will return an error if the MSR is unsupported, i.e. ctxt->ops->get_msr() will fail and the emulator will inject a #UD. Note, RDPID emulation also relies on RDTSCP being enabled in the guest, but this is a KVM bug and will eventually be fixed. Fixes: fb6d4d340e05 ("KVM: x86: emulate RDPID") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson Message-Id: <20210504171734.1434054-3-seanjc@google.com> Reviewed-by: Jim Mattson Reviewed-by: Reiji Watanabe Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/cpuid.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -572,7 +572,8 @@ static int __do_cpuid_func_emulated(stru case 7: entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX; entry->eax = 0; - entry->ecx = F(RDPID); + if (kvm_cpu_cap_has(X86_FEATURE_RDTSCP)) + entry->ecx = F(RDPID); ++array->nent; default: break;