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=-8.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,UNPARSEABLE_RELAY 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 A8EBFC2BBCF for ; Fri, 18 Dec 2020 01:28:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4E29B2395A for ; Fri, 18 Dec 2020 01:28:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727182AbgLRB2W (ORCPT ); Thu, 17 Dec 2020 20:28:22 -0500 Received: from belmont80srvr.owm.bell.net ([184.150.200.80]:33944 "EHLO mtlfep01.bell.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726851AbgLRB2V (ORCPT ); Thu, 17 Dec 2020 20:28:21 -0500 Received: from bell.net mtlfep01 184.150.200.30 by mtlfep01.bell.net with ESMTP id <20201218012740.FIXH120733.mtlfep01.bell.net@mtlspm01.bell.net>; Thu, 17 Dec 2020 20:27:40 -0500 Received: from starbug.dom ([67.68.23.153]) by mtlspm01.bell.net with ESMTP id <20201218012740.MLKT130487.mtlspm01.bell.net@starbug.dom>; Thu, 17 Dec 2020 20:27:40 -0500 Received: from starbug.dom (localhost [127.0.0.1]) by starbug.dom (Postfix) with ESMTP id BB5551EBAC6; Thu, 17 Dec 2020 20:27:38 -0500 (EST) From: Richard Herbert To: Paolo Bonzini , Sean Christopherson Cc: Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Ben Gardon Subject: [PATCH 0/4] KVM: x86/mmu: Bug fixes and cleanups in get_mmio_spte() Date: Thu, 17 Dec 2020 20:27:38 -0500 Message-ID: <2001245.9o76ZdvQCi@starbug.dom> In-Reply-To: <2346556.XAFRqVoOGU@starbug.dom> References: <20201218003139.2167891-1-seanjc@google.com> <2346556.XAFRqVoOGU@starbug.dom> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-CM-Analysis: v=2.4 cv=AbB0o1bG c=1 sm=1 tr=0 ts=5fdc058c a=Kmoo8mppt6dxYrHuFgrAcA==:117 a=Kmoo8mppt6dxYrHuFgrAcA==:17 a=kj9zAlcOel0A:10 a=zTNgK-yGK50A:10 a=ww6PLmxxykeOsXVbiHUA:9 a=CjuIK1q_8ugA:10 a=pHzHmUro8NiASowvMSCR:22 a=nt3jZW36AmriUCFCBwmW:22 X-CM-Envelope: MS4xfNEEu04CtsVlwGxMQ5DtGddkw/6a+MFkU8QWjQJfwp8dKIFe/Q7NwthaZuJ+Jv1xO7x5V0/T19wHB8nSF2kAn6myqlRv3UnQByhfdux1AGud6Uv6kQkM Vq3magofB7LyI7beJsF9voFs4AAYoWQZcpDgImNzXqJzBiTTsx6YyhvIa6dmt8F+rirnI8f/W+LE+8QdDc4AA/Vwl0c5z/VkuA3NeYk9ZQuUYLyhv5z8os5A Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Hi, Sean and all. Thanks so much for these. Very glad to report that the problem has been solved. I applied all four patches, recompiled kernel 5.10.1 and successfully launched a Qemu VM. Let's hope these will get merged into 5.10.2. Thanks again for the hard work and quick fix. Richard Herbert On Thursday, December 17, 2020 7:31:35 PM EST Sean Christopherson wrote: > Two fixes for bugs that were introduced along with the TDP MMU (though I > strongly suspect only the one reported by Richard, fixed in patch 2/4, is > hittable in practice). Two additional cleanup on top to try and make the > code a bit more readable and shave a few cycles. > > Sean Christopherson (4): > KVM: x86/mmu: Use -1 to flag an undefined spte in get_mmio_spte() > KVM: x86/mmu: Get root level from walkers when retrieving MMIO SPTE > KVM: x86/mmu: Use raw level to index into MMIO walks' sptes array > KVM: x86/mmu: Optimize not-present/MMIO SPTE check in get_mmio_spte() > > arch/x86/kvm/mmu/mmu.c | 53 +++++++++++++++++++++----------------- > arch/x86/kvm/mmu/tdp_mmu.c | 9 ++++--- > arch/x86/kvm/mmu/tdp_mmu.h | 4 ++- > 3 files changed, 39 insertions(+), 27 deletions(-)