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 598ACC433F5 for ; Fri, 11 Mar 2022 03:28:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346005AbiCKD3H (ORCPT ); Thu, 10 Mar 2022 22:29:07 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40834 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239978AbiCKD3G (ORCPT ); Thu, 10 Mar 2022 22:29:06 -0500 Received: from mail-pg1-x549.google.com (mail-pg1-x549.google.com [IPv6:2607:f8b0:4864:20::549]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8FE25EAC83 for ; Thu, 10 Mar 2022 19:28:04 -0800 (PST) Received: by mail-pg1-x549.google.com with SMTP id u75-20020a63794e000000b003810e49ae0eso203409pgc.3 for ; Thu, 10 Mar 2022 19:28:04 -0800 (PST) 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=XKkoV9WqAMW6txuBkF5Wd3rs0lT6dWVS/pJ+2/MRtag=; b=kufdfWVgYM9IzhcIFS2Zm75ZysbcrHo+Ft1gBPcwjP2xCCig08BOid5sNt+kBPWRCt Ovz6oGnz2qY/BmB4MJJ6UNIZ/H8ietBfYnn5sVsOHxpNc6NScHhfFnq4RBZEl8hehthK trb78KhZBvWAPpHIauti2B4oEYlX8VRIMdKqK9TcUZjfDEqlcGcrb1FeKztPVY/pOYf/ +a00MkCYl8XEqFqYIhj9SSHFrR02lJqzd4OSOOOyd0FfcAWXXF4yCKMU85lnOXpJEBCl 2cTtAImJkpdW04qL3ZFJe9E+JX4lhJcq8QiAauf9Re1Z7r1omuYMWrT3ntK69u4uP89q SeTQ== 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=XKkoV9WqAMW6txuBkF5Wd3rs0lT6dWVS/pJ+2/MRtag=; b=smYNc0XKhexPWVg6DjmLCZga/Uskde0nrTCd8DVG68wDJslxnWHMuIDunIxcvYkzOW x5QYjo7L2gvCbcuXnS/TA0Kp84bgOk5WLgKK4K/AwZ9E1nZCr0ixH5LbqM+/uUchgAtW ab2mOVH5M8daZtkBbRD8Hiq5us08QM1BiNDxWeN1cd4+eU6s2BQA4GJSHeQqmN22yt7R F4sPnI/LlDoK+dcyAXMbRGzniTlc3k8fNgqATbA2kBS34+1s/H4fGErp3kRkrCtu0v1N XkYcxAkd4KIeTbBf4I11A/zrYZ9RaqeEE2s4GJfVzF+5Ctr07OBL8e9+3lS+SS+yAWgV oikw== X-Gm-Message-State: AOAM532TFecurmCovMAtqwW/m44/yj1lyTxZePQ7zfpw3goqr6N+ngWL druWHPGv/mV1+44jy1yLq7VCd2HFwv8= X-Google-Smtp-Source: ABdhPJwIG2XZcUj85RKHGPmCh8wL09k3iIswXlIqpkv0ONOnCCRLF0z1lkYsbPsHDBhGQ3AIDKCVaQ/orcQ= X-Received: from seanjc.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:3e5]) (user=seanjc job=sendgmr) by 2002:a05:6a00:130e:b0:4f3:9654:266d with SMTP id j14-20020a056a00130e00b004f39654266dmr8042509pfu.59.1646969284051; Thu, 10 Mar 2022 19:28:04 -0800 (PST) Reply-To: Sean Christopherson Date: Fri, 11 Mar 2022 03:27:40 +0000 Message-Id: <20220311032801.3467418-1-seanjc@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.35.1.723.g4982287a31-goog Subject: [PATCH 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 (I truly thought this series was finished 10 commits and 3 days ago...). Nothing in here is all that urgent; all bugs tagged for stable have been around for multiple releases (years in most cases). Sean Christopherson (21): KVM: x86: Return immediately from x86_emulate_instruction() on code #DB 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: 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 | 33 +- arch/x86/kvm/emulate.c | 3 +- arch/x86/kvm/svm/nested.c | 100 ++--- arch/x86/kvm/svm/svm.c | 18 +- arch/x86/kvm/vmx/nested.c | 322 +++++++++----- arch/x86/kvm/vmx/sgx.c | 2 +- arch/x86/kvm/vmx/vmx.c | 53 ++- arch/x86/kvm/x86.c | 409 ++++++++++++------ arch/x86/kvm/x86.h | 10 +- tools/testing/selftests/kvm/.gitignore | 1 + tools/testing/selftests/kvm/Makefile | 1 + .../selftests/kvm/include/x86_64/svm_util.h | 5 +- .../selftests/kvm/include/x86_64/vmx.h | 51 +-- .../kvm/x86_64/nested_exceptions_test.c | 307 +++++++++++++ 15 files changed, 914 insertions(+), 403 deletions(-) create mode 100644 tools/testing/selftests/kvm/x86_64/nested_exceptions_test.c base-commit: 4a204f7895878363ca8211f50ec610408c8c70aa -- 2.35.1.723.g4982287a31-goog