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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BF751CCA47A for ; Tue, 14 Jun 2022 20:47:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237537AbiFNUrq (ORCPT ); Tue, 14 Jun 2022 16:47:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36618 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229585AbiFNUri (ORCPT ); Tue, 14 Jun 2022 16:47:38 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E818E1D0F3 for ; Tue, 14 Jun 2022 13:47:36 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id a68-20020a25ca47000000b006605f788ff1so8482643ybg.16 for ; Tue, 14 Jun 2022 13:47:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=reply-to:date:message-id:mime-version:subject:from:to:cc; bh=RNfsBnrb019GwwlDncDGa0smr28pomq7mA55AJKJhHI=; b=R325LsRZneFNEFs8J6A6K9NT69ICE7hR+z6FsW/5Db9t8H6xLdqgyEpeRzkOBdLCO/ XQCmFcsCKJt7FSotMJUlI6ZBcOVL9BatykBhuM1yBHYmz3ZilAF4/D4eC2XkhNHdtAkJ scgUUyd4ok2n2uXyg2qcJSVX809jw/dkHJEm8qde54teS95v+M3B8e5rIo/QaVzOtoSv Rcqv2Rgt2kvMXuS1BvxVEvuxOy3DwocOX33yLWhfR3rpGcqZcPjMDZCQlgjJYTKE7W54 rCoffxIBjX7bY2L7ZhgeeEBK/6eTvKCUKnqePEQJHcg9mRv9oHzqhWmq9vLROZhuOVCB S3yg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:reply-to:date:message-id:mime-version:subject :from:to:cc; bh=RNfsBnrb019GwwlDncDGa0smr28pomq7mA55AJKJhHI=; b=lGm8gVwrxV43gIxprJOZ564CKrP1jKGr90Mumn5aULH3gr0D0WsN1JPR03iUaIdVvg 57Y+1HnvIiYY34b5k/cCXpS+z1jxQqbl4QtVOna4E1qq29XKLdNuZ7rA06W7PgS7QzHR vHXyAlG9CG1kR0lUC/1vsRHaY78PyTODKvfYyCGrnTfALc1ERXRJZ677qefP7GOlMtOb c1C715pJ0N+xBEBd9XAFFpRFJHcMepm+NglBBDXNaAdb4loOLqG+eidtqRFJ+eo1GogR bajs0ZmTlDDRNoqfxxDZuLIqxBAVXkqNS8B8Heohd6cGbzxFSkc45R0hQUJ493bUZt9f SNdw== X-Gm-Message-State: AJIora98auvagY0GtHmRmAp78Lz/wzSgPqQ/HwJzIFFcdGfEOiQM1G2y PGMbKVeN3SAj3PY+d86P42PAu8WDVGs= X-Google-Smtp-Source: AGRyM1vaT5geIv0+nQuGaH5hx7l6hUj5FbIN6ax9c/UTf8qAI7MTavn23/SMXsJJTDkFsNPPjKgejO8Ibpo= X-Received: from seanjc.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:3e5]) (user=seanjc job=sendgmr) by 2002:a81:260a:0:b0:300:1729:7654 with SMTP id m10-20020a81260a000000b0030017297654mr7643645ywm.125.1655239656113; Tue, 14 Jun 2022 13:47:36 -0700 (PDT) Reply-To: Sean Christopherson Date: Tue, 14 Jun 2022 20:47:09 +0000 Message-Id: <20220614204730.3359543-1-seanjc@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.36.1.476.g0c4daa206d-goog Subject: [PATCH v2 00/21] KVM: x86: Event/exception fixes and cleanups From: Sean Christopherson To: Paolo Bonzini Cc: Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Oliver Upton , Peter Shier Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The main goal of this series is to fix KVM's longstanding bug of not honoring L1's exception intercepts wants when handling an exception that occurs during delivery of a different exception. E.g. if L0 and L1 are using shadow paging, and L2 hits a #PF, and then hits another #PF while vectoring the first #PF due to _L1_ not having a shadow page for the IDT, KVM needs to check L1's intercepts before morphing the #PF => #PF => #DF so that the #PF is routed to L1, not injected into L2 as a #DF. nVMX has hacked around the bug for years by overriding the #PF injector for shadow paging to go straight to VM-Exit, and nSVM has started doing the same. The hacks mostly work, but they're incomplete, confusing, and lead to other hacky code, e.g. bailing from the emulator because #PF injection forced a VM-Exit and suddenly KVM is back in L1. Everything leading up to that are related fixes and cleanups I encountered along the way; some through code inspection, some through tests. v2: - Rebased to kvm/queue (commit 8baacf67c76c) + selftests CPUID overhaul. https://lore.kernel.org/all/20220614200707.3315957-1-seanjc@google.com - Treat KVM_REQ_TRIPLE_FAULT as a pending exception. v1: https://lore.kernel.org/all/20220311032801.3467418-1-seanjc@google.com Sean Christopherson (21): KVM: nVMX: Unconditionally purge queued/injected events on nested "exit" KVM: VMX: Drop bits 31:16 when shoving exception error code into VMCS KVM: x86: Don't check for code breakpoints when emulating on exception KVM: nVMX: Treat General Detect #DB (DR7.GD=1) as fault-like KVM: nVMX: Prioritize TSS T-flag #DBs over Monitor Trap Flag KVM: x86: Treat #DBs from the emulator as fault-like (code and DR7.GD=1) KVM: x86: Use DR7_GD macro instead of open coding check in emulator KVM: nVMX: Ignore SIPI that arrives in L2 when vCPU is not in WFS KVM: nVMX: Unconditionally clear mtf_pending on nested VM-Exit KVM: VMX: Inject #PF on ENCLS as "emulated" #PF KVM: x86: Rename kvm_x86_ops.queue_exception to inject_exception KVM: x86: Make kvm_queued_exception a properly named, visible struct KVM: x86: Formalize blocking of nested pending exceptions KVM: x86: Use kvm_queue_exception_e() to queue #DF KVM: x86: Hoist nested event checks above event injection logic KVM: x86: Evaluate ability to inject SMI/NMI/IRQ after potential VM-Exit KVM: x86: Morph pending exceptions to pending VM-Exits at queue time KVM: x86: Treat pending TRIPLE_FAULT requests as pending exceptions KVM: VMX: Update MTF and ICEBP comments to document KVM's subtle behavior KVM: selftests: Use uapi header to get VMX and SVM exit reasons/codes KVM: selftests: Add an x86-only test to verify nested exception queueing arch/x86/include/asm/kvm-x86-ops.h | 2 +- arch/x86/include/asm/kvm_host.h | 35 +- arch/x86/kvm/emulate.c | 3 +- arch/x86/kvm/svm/nested.c | 102 ++--- arch/x86/kvm/svm/svm.c | 18 +- arch/x86/kvm/vmx/nested.c | 319 +++++++++----- arch/x86/kvm/vmx/sgx.c | 2 +- arch/x86/kvm/vmx/vmx.c | 53 ++- arch/x86/kvm/x86.c | 404 +++++++++++------- arch/x86/kvm/x86.h | 11 +- tools/testing/selftests/kvm/.gitignore | 1 + tools/testing/selftests/kvm/Makefile | 1 + .../selftests/kvm/include/x86_64/svm_util.h | 7 +- .../selftests/kvm/include/x86_64/vmx.h | 51 +-- .../kvm/x86_64/nested_exceptions_test.c | 295 +++++++++++++ 15 files changed, 886 insertions(+), 418 deletions(-) create mode 100644 tools/testing/selftests/kvm/x86_64/nested_exceptions_test.c base-commit: 816967202161955f398ce379f9cbbedcb1eb03cb -- 2.36.1.476.g0c4daa206d-goog