From patchwork Wed Aug 18 00:12:05 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 12442355 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=-21.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL 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 96F9FC432BE for ; Wed, 18 Aug 2021 00:12:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 73C7260EBC for ; Wed, 18 Aug 2021 00:12:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237103AbhHRAM7 (ORCPT ); Tue, 17 Aug 2021 20:12:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49192 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235588AbhHRAM6 (ORCPT ); Tue, 17 Aug 2021 20:12:58 -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 8F395C061796 for ; Tue, 17 Aug 2021 17:12:24 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id c63-20020a25e5420000b0290580b26e708aso949886ybh.12 for ; Tue, 17 Aug 2021 17:12:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=reply-to:date:message-id:mime-version:subject:from:to:cc; bh=JTnvoGQPkzSY6sftzgGOupURPM7Ep9m5Wy1FXJgvwt8=; b=fyeUao6f185gl09ZYsAcdA7yqynUAarWJxtZWYjEguvdRD3P7FagvzAviDCjWFv9rL hkTapS9n0MejNBYX2Q5yho2bHtiNxihusqY+CxIRaDELLoNGX+rLqUW5lJrnEo/Mnm0e tdASNb+sSeLR5tAQ8VguxhX7xu/etGncJN6MqDGLgROWk+szWdS+QKryOwUk7KtLD9kc VIB77hKdU4R/GCrKDGfJV45g5i0FA1HckPWMpfpc96fmGXzvuG0a3+dtXdvgVNUn85ch 0fl8hUM/hx3+Jt5MkdC3np01fB7+YS8SSyrKtslPuKN3R0rpXVrltaB4IU7mkT2jcj3C EtqA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:reply-to:date:message-id:mime-version:subject :from:to:cc; bh=JTnvoGQPkzSY6sftzgGOupURPM7Ep9m5Wy1FXJgvwt8=; b=FjijigpSSoJUgxw8FPMZRajeiDXdMrufcpEaYGy9rTYKgQABRXxONmISNId6ItJchS lkETqu3PhU6F5lb+vE8LwJ9x50aMwJwb68wKmKAvQlRWnjSr0kv9WlYLfQL/aBLF8ulz deWinhZbICxNgJH8VvvVOqsTW8WiCBuRB8jYTP9ye2RVGknLahpMtudT+OcYdNwndBHI ImV3iwi+VRdN6aCgEXmc2/pHLs8QhOb+3cl+LSKicf8qAG1In+8PtZAS487hTuWR8Urs DjrC5QugCfVldyKjRcOFhyR8RpT+DT4rU3/zIMIwEIbvGax39fL6cHU6btgO9akviSDE y8+Q== X-Gm-Message-State: AOAM531vWradzpr6vxFH/bHXHYr5gD4DKhLtSXzvuoYApHOv+sM2GgNm aP2WarGGw61LjUVCx7K+YtFksCAPxQU= X-Google-Smtp-Source: ABdhPJx/sMOLc7HCSgjqqqa43Z4/KNb0h6Qo8TurrCfZhkWk410D/oOp9imaDI4DVCS6cpPHQf2wmOXKS3s= X-Received: from seanjc798194.pdx.corp.google.com ([2620:15c:90:200:158e:55a:74dd:5197]) (user=seanjc job=sendgmr) by 2002:a25:7743:: with SMTP id s64mr7874463ybc.214.1629245543687; Tue, 17 Aug 2021 17:12:23 -0700 (PDT) Reply-To: Sean Christopherson Date: Tue, 17 Aug 2021 17:12:05 -0700 Message-Id: <20210818001210.4073390-1-seanjc@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.33.0.rc1.237.g0d66db33f3-goog Subject: [PATCH 0/5] KVM: rseq: Fix and a test for a KVM+rseq bug From: Sean Christopherson To: Russell King , Catalin Marinas , Will Deacon , Guo Ren , Thomas Bogendoerfer , Michael Ellerman , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , Oleg Nesterov , Steven Rostedt , Ingo Molnar , Thomas Gleixner , Peter Zijlstra , Andy Lutomirski , Mathieu Desnoyers , "Paul E. McKenney" , Boqun Feng , Paolo Bonzini , Shuah Khan Cc: Benjamin Herrenschmidt , Paul Mackerras , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-csky@vger.kernel.org, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org, Peter Foley , Shakeel Butt , Sean Christopherson , Ben Gardon Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Patch 1 fixes a KVM+rseq bug where KVM's handling of TIF_NOTIFY_RESUME, e.g. for task migration, clears the flag without informing rseq and leads to stale data in userspace's rseq struct. Patch 2 is a cleanup to try and make future bugs less likely. It's also a baby step towards moving and renaming tracehook_notify_resume() since it has nothing to do with tracing. It kills me to not do the move/rename as part of this series, but having a dedicated series/discussion seems more appropriate given the sheer number of architectures that call tracehook_notify_resume() and the lack of an obvious home for the code. Patch 3 is a fix/cleanup to stop overriding x86's unistd_{32,64}.h when the include path (intentionally) omits tools' uapi headers. KVM's selftests do exactly that so that they can pick up the uapi headers from the installed kernel headers, and still use various tools/ headers that mirror kernel code, e.g. linux/types.h. This allows the new test in patch 4 to reference __NR_rseq without having to manually define it. Patch 4 is a regression test for the KVM+rseq bug. Patch 5 is a cleanup made possible by patch 3. Sean Christopherson (5): KVM: rseq: Update rseq when processing NOTIFY_RESUME on xfer to KVM guest entry: rseq: Call rseq_handle_notify_resume() in tracehook_notify_resume() tools: Move x86 syscall number fallbacks to .../uapi/ KVM: selftests: Add a test for KVM_RUN+rseq to detect task migration bugs KVM: selftests: Remove __NR_userfaultfd syscall fallback arch/arm/kernel/signal.c | 1 - arch/arm64/kernel/signal.c | 1 - arch/csky/kernel/signal.c | 4 +- arch/mips/kernel/signal.c | 4 +- arch/powerpc/kernel/signal.c | 4 +- arch/s390/kernel/signal.c | 1 - include/linux/tracehook.h | 2 + kernel/entry/common.c | 4 +- kernel/rseq.c | 4 +- .../x86/include/{ => uapi}/asm/unistd_32.h | 0 .../x86/include/{ => uapi}/asm/unistd_64.h | 3 - tools/testing/selftests/kvm/.gitignore | 1 + tools/testing/selftests/kvm/Makefile | 3 + tools/testing/selftests/kvm/rseq_test.c | 131 ++++++++++++++++++ 14 files changed, 143 insertions(+), 20 deletions(-) rename tools/arch/x86/include/{ => uapi}/asm/unistd_32.h (100%) rename tools/arch/x86/include/{ => uapi}/asm/unistd_64.h (83%) create mode 100644 tools/testing/selftests/kvm/rseq_test.c