From patchwork Wed Apr 1 16:17:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 228316 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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 CCF05C43331 for ; Wed, 1 Apr 2020 16:53:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A3E66206E9 for ; Wed, 1 Apr 2020 16:53:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585760026; bh=mtfkkCt5SFGhLPN1U7MCkZ3jcSv/3FhZA5jJUw2+TxU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=cpbxCkaxLvbFKotWOpbc/0+W5kZl51+JTZyEjAiJ5gq7BXPHZIAG0aeAvyvdhBMLI t1lpJE98HA8DNwcJ0PIooIeEKUu9oP6KOdIDAUHS0entq/Ead05AkCqC0Tq0OdI7yk bSidNUozc5pysloQ8QQTOXiIU1r740UmF/sNjATI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732940AbgDAQxm (ORCPT ); Wed, 1 Apr 2020 12:53:42 -0400 Received: from mail.kernel.org ([198.145.29.99]:57892 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388328AbgDAQbj (ORCPT ); Wed, 1 Apr 2020 12:31:39 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 228B12063A; Wed, 1 Apr 2020 16:31:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585758698; bh=mtfkkCt5SFGhLPN1U7MCkZ3jcSv/3FhZA5jJUw2+TxU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dOXJbAU6S/pg/fW0wQ4ib5dnwpjCZgDCWwUd1azR5hfbxGIG5TvJsslwslNSCLBVP Spl2WOM1ig9nNXwnF3cv9xNapHciXwP1g8QwBfpewbrf2DdpPNSn8f5kglBFpXcIzu TfC0vzxNgdgLKdqL3yjMrOxfXLtXVqK4M3/+my6s= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vitaly Kuznetsov , Sean Christopherson , =?utf-8?b?UmFkaW0gS3LEjW3DocWZ?= , Sasha Levin Subject: [PATCH 4.4 47/91] KVM: VMX: Do not allow reexecute_instruction() when skipping MMIO instr Date: Wed, 1 Apr 2020 18:17:43 +0200 Message-Id: <20200401161529.578652949@linuxfoundation.org> X-Mailer: git-send-email 2.26.0 In-Reply-To: <20200401161512.917494101@linuxfoundation.org> References: <20200401161512.917494101@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Sean Christopherson [ Upstream commit c4409905cd6eb42cfd06126e9226b0150e05a715 ] Re-execution after an emulation decode failure is only intended to handle a case where two or vCPUs race to write a shadowed page, i.e. we should never re-execute an instruction as part of MMIO emulation. As handle_ept_misconfig() is only used for MMIO emulation, it should pass EMULTYPE_NO_REEXECUTE when using the emulator to skip an instr in the fast-MMIO case where VM_EXIT_INSTRUCTION_LEN is invalid. And because the cr2 value passed to x86_emulate_instruction() is only destined for use when retrying or reexecuting, we can simply call emulate_instruction(). Fixes: d391f1207067 ("x86/kvm/vmx: do not use vm-exit instruction length for fast MMIO when running nested") Cc: Vitaly Kuznetsov Signed-off-by: Sean Christopherson Cc: stable@vger.kernel.org Signed-off-by: Radim Krčmář Signed-off-by: Sasha Levin --- arch/x86/kvm/vmx.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 78daf891abec8..2634b45562026 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -6187,8 +6187,8 @@ static int handle_ept_misconfig(struct kvm_vcpu *vcpu) return 1; } else - return x86_emulate_instruction(vcpu, gpa, EMULTYPE_SKIP, - NULL, 0) == EMULATE_DONE; + return emulate_instruction(vcpu, EMULTYPE_SKIP) == + EMULATE_DONE; } ret = handle_mmio_page_fault(vcpu, gpa, true);