From patchwork Tue Mar 17 10:55:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 229351 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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, 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 D4EBCC18E5B for ; Tue, 17 Mar 2020 10:58:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A4D512071C for ; Tue, 17 Mar 2020 10:58:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584442737; bh=TOkH5WlSFQyVZXCFkpzAVTVt8FbZuTxzjwijMBTQ9G4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=1ih+M+sFw3jR50eZ7q/TjIFSM8UtLsol6iwlzfiHxmWw9kERj/hyBJx+kj6+ys5kO bqbQF2RwQpWwIPmB4iGtiBGqx/V/JIjWd9F+sr9EItNXgvrXOXdTMIaOHN9k+fV21Y g9AN9PHzbb2EEpVw4lRQyEq6Lr/p7VvJxOA6tPHQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726947AbgCQK6w (ORCPT ); Tue, 17 Mar 2020 06:58:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:37042 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727338AbgCQK6t (ORCPT ); Tue, 17 Mar 2020 06:58:49 -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 5AB8C20719; Tue, 17 Mar 2020 10:58:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584442728; bh=TOkH5WlSFQyVZXCFkpzAVTVt8FbZuTxzjwijMBTQ9G4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VfPFAgofe/lk29H+GYXquqhwJEZykZ1kUxXBJZmt9TzEDXamQwqiGwLsftcQLugW7 h4MWJPVAjnLZRWWXA/LNc1QrMHItC5TljdB85/hCe6kdGic+xSaDxnm1xK9EL95qoi 47+/+TNRUjO+K+G+wnyqO5+kZT8Pwce6+DEIRq64= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Paolo Bonzini , Vitaly Kuznetsov , Sean Christopherson Subject: [PATCH 4.19 60/89] KVM: x86: clear stale x86_emulate_ctxt->intercept value Date: Tue, 17 Mar 2020 11:55:09 +0100 Message-Id: <20200317103306.803235020@linuxfoundation.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200317103259.744774526@linuxfoundation.org> References: <20200317103259.744774526@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: Vitaly Kuznetsov commit 342993f96ab24d5864ab1216f46c0b199c2baf8e upstream. After commit 07721feee46b ("KVM: nVMX: Don't emulate instructions in guest mode") Hyper-V guests on KVM stopped booting with: kvm_nested_vmexit: rip fffff802987d6169 reason EPT_VIOLATION info1 181 info2 0 int_info 0 int_info_err 0 kvm_page_fault: address febd0000 error_code 181 kvm_emulate_insn: 0:fffff802987d6169: f3 a5 kvm_emulate_insn: 0:fffff802987d6169: f3 a5 FAIL kvm_inj_exception: #UD (0x0) "f3 a5" is a "rep movsw" instruction, which should not be intercepted at all. Commit c44b4c6ab80e ("KVM: emulate: clean up initializations in init_decode_cache") reduced the number of fields cleared by init_decode_cache() claiming that they are being cleared elsewhere, 'intercept', however, is left uncleared if the instruction does not have any of the "slow path" flags (NotImpl, Stack, Op3264, Sse, Mmx, CheckPerm, NearBranch, No16 and of course Intercept itself). Fixes: c44b4c6ab80e ("KVM: emulate: clean up initializations in init_decode_cache") Fixes: 07721feee46b ("KVM: nVMX: Don't emulate instructions in guest mode") Cc: stable@vger.kernel.org Suggested-by: Paolo Bonzini Signed-off-by: Vitaly Kuznetsov Reviewed-by: Sean Christopherson Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/emulate.c | 1 + 1 file changed, 1 insertion(+) --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -5112,6 +5112,7 @@ int x86_decode_insn(struct x86_emulate_c ctxt->fetch.ptr = ctxt->fetch.data; ctxt->fetch.end = ctxt->fetch.data + insn_len; ctxt->opcode_len = 1; + ctxt->intercept = x86_intercept_none; if (insn_len > 0) memcpy(ctxt->fetch.data, insn, insn_len); else {