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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 E8884C433F4 for ; Thu, 20 Sep 2018 16:32:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9413221526 for ; Thu, 20 Sep 2018 16:32:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9413221526 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387749AbeITWQh (ORCPT ); Thu, 20 Sep 2018 18:16:37 -0400 Received: from mx1.redhat.com ([209.132.183.28]:33912 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726163AbeITWQh (ORCPT ); Thu, 20 Sep 2018 18:16:37 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id DEC5E81106; Thu, 20 Sep 2018 16:32:17 +0000 (UTC) Received: from [10.36.117.122] (ovpn-117-122.ams2.redhat.com [10.36.117.122]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 1143E600C8; Thu, 20 Sep 2018 16:32:11 +0000 (UTC) Subject: Re: [PATCH RESEND] kvm/x86: propagate fetch fault into guest To: Sean Christopherson , Peng Hao , rkrcmar@redhat.com, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, x86@kernel.org, peng.hao2@zte.com, Peng Hao References: <1537311828-4547-1-git-send-email-penghao122@sina.com.cn> <1537367635.9937.4.camel@intel.com> From: Paolo Bonzini Openpgp: preference=signencrypt Autocrypt: addr=pbonzini@redhat.com; prefer-encrypt=mutual; keydata= xsEhBFRCcBIBDqDGsz4K0zZun3jh+U6Z9wNGLKQ0kSFyjN38gMqU1SfP+TUNQepFHb/Gc0E2 CxXPkIBTvYY+ZPkoTh5xF9oS1jqI8iRLzouzF8yXs3QjQIZ2SfuCxSVwlV65jotcjD2FTN04 hVopm9llFijNZpVIOGUTqzM4U55sdsCcZUluWM6x4HSOdw5F5Utxfp1wOjD/v92Lrax0hjiX DResHSt48q+8FrZzY+AUbkUS+Jm34qjswdrgsC5uxeVcLkBgWLmov2kMaMROT0YmFY6A3m1S P/kXmHDXxhe23gKb3dgwxUTpENDBGcfEzrzilWueOeUWiOcWuFOed/C3SyijBx3Av/lbCsHU Vx6pMycNTdzU1BuAroB+Y3mNEuW56Yd44jlInzG2UOwt9XjjdKkJZ1g0P9dwptwLEgTEd3Fo UdhAQyRXGYO8oROiuh+RZ1lXp6AQ4ZjoyH8WLfTLf5g1EKCTc4C1sy1vQSdzIRu3rBIjAvnC tGZADei1IExLqB3uzXKzZ1BZ+Z8hnt2og9hb7H0y8diYfEk2w3R7wEr+Ehk5NQsT2MPI2QBd wEv1/Aj1DgUHZAHzG1QN9S8wNWQ6K9DqHZTBnI1hUlkp22zCSHK/6FwUCuYp1zcAEQEAAc0f UGFvbG8gQm9uemluaSA8Ym9uemluaUBnbnUub3JnPsLBTQQTAQIAIwUCVEJ7AwIbAwcLCQgH AwIBBhUIAgkKCwQWAgMBAh4BAheAAAoJEH4VEAzNNmmxNcwOniaZVLsuy1lW/ntYCA0Caz0i sHpmecK8aWlvL9wpQCk4GlOX9L1emyYXZPmzIYB0IRqmSzAlZxi+A2qm9XOxs5gJ2xqMEXX5 FMtUH3kpkWWJeLqe7z0EoQdUI4EG988uv/tdZyqjUn2XJE+K01x7r3MkUSFz/HZKZiCvYuze VlS0NTYdUt5jBXualvAwNKfxEkrxeHjxgdFHjYWhjflahY7TNRmuqPM/Lx7wAuyoDjlYNE40 Z+Kun4/KjMbjgpcF4Nf3PJQR8qXI6p3so2qsSn91tY7DFSJO6v2HwFJkC2jU95wxfNmTEUZc znXahYbVOwCDJRuPrE5GKFd/XJU9u5hNtr/uYipHij01WXal2cce1S5mn1/HuM1yo1u8xdHy IupCd57EWI948e8BlhpujUCU2tzOb2iYS0kpmJ9/oLVZrOcSZCcCl2P0AaCAsj59z2kwQS9D du0WxUs8waso0Qq6tDEHo8yLCOJDzSz4oojTtWe4zsulVnWV+wu70AioemAT8S6JOtlu60C5 dHgQUD1Tp+ReXpDKXmjbASJx4otvW0qah3o6JaqO79tbDqIvncu3tewwp6c85uZd48JnIOh3 utBAu684nJakbbvZUGikJfxd887ATQRUQnHuAQgAx4dxXO6/Zun0eVYOnr5GRl76+2UrAAem Vv9Yfn2PbDIbxXqLff7oyVJIkw4WdhQIIvvtu5zH24iYjmdfbg8iWpP7NqxUQRUZJEWbx2CR wkMHtOmzQiQ2tSLjKh/cHeyFH68xjeLcinR7jXMrHQK+UCEw6jqi1oeZzGvfmxarUmS0uRuf fAb589AJW50kkQK9VD/9QC2FJISSUDnRC0PawGSZDXhmvITJMdD4TjYrePYhSY4uuIV02v02 8TVAaYbIhxvDY0hUQE4r8ZbGRLn52bEzaIPgl1p/adKfeOUeMReg/CkyzQpmyB1TSk8lDMxQ zCYHXAzwnGi8WU9iuE1P0wARAQABwsEzBBgBAgAJBQJUQnHuAhsMAAoJEH4VEAzNNmmxp1EO oJy0uZggJm7gZKeJ7iUpeX4eqUtqelUw6gU2daz2hE/jsxsTbC/w5piHmk1H1VWDKEM4bQBT uiJ0bfo55SWsUNN+c9hhIX+Y8LEe22izK3w7mRpvGcg+/ZRG4DEMHLP6JVsv5GMpoYwYOmHn plOzCXHvmdlW0i6SrMsBDl9rw4AtIa6bRwWLim1lQ6EM3PWifPrWSUPrPcw4OLSwFk0CPqC4 HYv/7ZnASVkR5EERFF3+6iaaVi5OgBd81F1TCvCX2BEyIDRZLJNvX3TOd5FEN+lIrl26xecz 876SvcOb5SL5SKg9/rCBufdPSjojkGFWGziHiFaYhbuI2E+NfWLJtd+ZvWAAV+O0d8vFFSvr iy9enJ8kxJwhC0ECbSKFY+W1eTIhMD3aeAKY90drozWEyHhENf4l/V+Ja5vOnW+gCDQkGt2Y 1lJAPPSIqZKvHzGShdh8DduC0U3xYkfbGAUvbxeepjgzp0uEnBXfPTy09JGpgWbg0w91GyfT /ujKaGd4vxG2Ei+MMNDmS1SMx7wu0evvQ5kT9NPzyq8R2GIhVSiAd2jioGuTjX6AZCFv3ToO 53DliFMkVTecLptsXaesuUHgL9dKIfvpm+rNXRn9wAwGjk0X/A== Message-ID: Date: Thu, 20 Sep 2018 18:32:10 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <1537367635.9937.4.camel@intel.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Thu, 20 Sep 2018 16:32:18 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 19/09/2018 16:33, Sean Christopherson wrote: > On Tue, 2018-09-18 at 19:03 -0400, Peng Hao wrote: >> From: Peng Hao >> >> When handling ept misconfig exit, it will call emulate instruction >> with insn_len = 0. The decode instruction function may return a fetch >> fault and should propagate to guest. > > What fault is encountered, e.g. #PF, #UD, etc...?  Something like a > #UD at this point should result in an exit to userspace as it means > KVM was unable to emulate an instruction that was successfully > decoded by hardware. If it's the same bug as https://lore.kernel.org/patchwork/patch/850077/ it would be a #PF. Paolo >> The problem will result to emulation fail. >> KVM internal error. Suberror: 1 >> emulation failure >> EAX=f81a0024 EBX=f6a07000 ECX=f6a0737c EDX=f8be0118 >> ESI=f6a0737c EDI=00000021 EBP=f6929f98 ESP=f6929f98 >> EIP=f8bdd141 EFL=00010086 [--S--P-] CPL=0 II=0 A20=1 SMM=0 HLT=0 >> ES =007b 00000000 ffffffff 00c0f300 DPL=3 DS   [-WA] >> CS =0060 00000000 ffffffff 00c09b00 DPL=0 CS32 [-RA] >> SS =0068 00000000 ffffffff 00c09300 DPL=0 DS   [-WA] >> DS =007b 00000000 ffffffff 00c0f300 DPL=3 DS   [-WA] >> FS =00d8 2c044000 ffffffff 00809300 DPL=0 DS16 [-WA] >> GS =0033 081a44c8 01000fff 00d0f300 DPL=3 DS   [-WA] >> LDT=0000 00000000 ffffffff 00000000 >> TR =0080 f6ea0c80 0000206b 00008b00 DPL=0 TSS32-busy >> GDT=     f6e99000 000000ff >> IDT=     fffbb000 000007ff >> CR0=80050033 CR2=b757d000 CR3=35d31000 CR4=001406d0 >> >> Signed-off-by: Peng Hao >> Reviewed-by: Jiang Biao >> --- >>  arch/x86/kvm/emulate.c | 5 ++++- >>  arch/x86/kvm/x86.c     | 4 +++- >>  2 files changed, 7 insertions(+), 2 deletions(-) >> >> diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c >> index 106482d..aecf9a72 100644 >> --- a/arch/x86/kvm/emulate.c >> +++ b/arch/x86/kvm/emulate.c >> @@ -5105,8 +5105,11 @@ int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len) >>   memcpy(ctxt->fetch.data, insn, insn_len); >>   else { >>   rc = __do_insn_fetch_bytes(ctxt, 1); >> - if (rc != X86EMUL_CONTINUE) >> + if (rc != X86EMUL_CONTINUE) { >> + if (rc == X86EMUL_PROPAGATE_FAULT) >> + ctxt->have_exception = true; >>   return rc; >> + } >>   } >>   >>   switch (mode) { >> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c >> index 542f631..27072e1 100644 >> --- a/arch/x86/kvm/x86.c >> +++ b/arch/x86/kvm/x86.c >> @@ -6188,8 +6188,10 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu, >>   if (reexecute_instruction(vcpu, cr2, write_fault_to_spt, >>   emulation_type)) >>   return EMULATE_DONE; >> - if (ctxt->have_exception && inject_emulated_exception(vcpu)) >> + if (ctxt->have_exception) { >> + inject_emulated_exception(vcpu); >>   return EMULATE_DONE; >> + } >>   if (emulation_type & EMULTYPE_SKIP) >>   return EMULATE_FAIL; >>   return handle_emulation_failure(vcpu, emulation_type);