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 C90D1C433EF for ; Fri, 1 Jul 2022 14:29:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232431AbiGAO3Y (ORCPT ); Fri, 1 Jul 2022 10:29:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39472 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232302AbiGAO2Q (ORCPT ); Fri, 1 Jul 2022 10:28:16 -0400 Received: from mail-ej1-x64a.google.com (mail-ej1-x64a.google.com [IPv6:2a00:1450:4864:20::64a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 550ED60512 for ; Fri, 1 Jul 2022 07:25:01 -0700 (PDT) Received: by mail-ej1-x64a.google.com with SMTP id sa13-20020a1709076d0d00b0072a8791298aso839774ejc.7 for ; Fri, 01 Jul 2022 07:25:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=iJzH9xEnS9/oOC6mna7qxAN7hxj/kW7q3+xewUipeVQ=; b=RVivBlTR5bofeeHvx5RVBIPcMBigWOGTJx99w3m0vNDpNl5jHHs78XLLZXJxwe/+5i Us8Tqq85fBL1Q5tr4+EcRexPCYSh2izwsFNvThnyX0KBGJJYkcgwY30jVffqFmHDyD67 iZwEMX65hRenyyZFN+5/nfXdDGFpZ/LxSRWWqwwJ98IqgGy6Kzh5LAUVX4FbaxvP4YUk hrM1kwNT2keDEX5k5YiHsQtL6cxITuwX4ilkbVNOdYayhHQrA0ShA+8wI4qSIzydqax0 A0kabSTooD72wkvYqsGaqrmOnGcagimMwdacJ5Qqil/EEyGsz4qLQDSwcoHCbI3XLzmR q9Jg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=iJzH9xEnS9/oOC6mna7qxAN7hxj/kW7q3+xewUipeVQ=; b=t4VjUsNymQjw2Cy+PlqdsjzRMa5wbpYqvRF3FW+A+uowt8caJ36sXbbNaSSY76wlQk faL3usjneUeTSf6fqQndKz7IhKY4eD7hwwBwG0oWvUtXhB85poyqSpV8HgPqrJU6fQYy YyR1iv44SsPR5FUrK69G1MrVwlOPKc90Zv/9jHirN7jTKKuywGpnwkCp748tRSpGUu1z 9ycQTtS+rRGe7/ejruGKXEk3/g0bXeW4DvWLsrRHQdFxlFwRPQYjbu5shqYX3C7LnbzC A6DYgiMJyrhWCwEIECNtUZyBI9cN+EGwNxTXG/pnYLtTzK9/ITX6dpKVXgwbcv2HcKbb j9pw== X-Gm-Message-State: AJIora9aotcjlNAyD755dCG5LsEftS81XQjD6IbED9vPjF8Nfn35pTwq e7em2dqyuA7AFyG69s8LD3owxdsXqsg= X-Google-Smtp-Source: AGRyM1tdwiFJ3qF9MS38GxgbW52KC3MGvTZOZgXwa4g5wlNolLgvT8yqZo+xIYJSOE8/WPEzc6X2ND/yzmI= X-Received: from glider.muc.corp.google.com ([2a00:79e0:9c:201:a6f5:f713:759c:abb6]) (user=glider job=sendgmr) by 2002:a17:907:3e13:b0:726:eebc:3461 with SMTP id hp19-20020a1709073e1300b00726eebc3461mr14278594ejc.528.1656685487802; Fri, 01 Jul 2022 07:24:47 -0700 (PDT) Date: Fri, 1 Jul 2022 16:22:58 +0200 In-Reply-To: <20220701142310.2188015-1-glider@google.com> Message-Id: <20220701142310.2188015-34-glider@google.com> Mime-Version: 1.0 References: <20220701142310.2188015-1-glider@google.com> X-Mailer: git-send-email 2.37.0.rc0.161.g10f37bed90-goog Subject: [PATCH v4 33/45] x86: kmsan: disable instrumentation of unsupported code From: Alexander Potapenko To: glider@google.com Cc: Alexander Viro , Alexei Starovoitov , Andrew Morton , Andrey Konovalov , Andy Lutomirski , Arnd Bergmann , Borislav Petkov , Christoph Hellwig , Christoph Lameter , David Rientjes , Dmitry Vyukov , Eric Dumazet , Greg Kroah-Hartman , Herbert Xu , Ilya Leoshkevich , Ingo Molnar , Jens Axboe , Joonsoo Kim , Kees Cook , Marco Elver , Mark Rutland , Matthew Wilcox , "Michael S. Tsirkin" , Pekka Enberg , Peter Zijlstra , Petr Mladek , Steven Rostedt , Thomas Gleixner , Vasily Gorbik , Vegard Nossum , Vlastimil Babka , kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org Instrumenting some files with KMSAN will result in kernel being unable to link, boot or crashing at runtime for various reasons (e.g. infinite recursion caused by instrumentation hooks calling instrumented code again). Completely omit KMSAN instrumentation in the following places: - arch/x86/boot and arch/x86/realmode/rm, as KMSAN doesn't work for i386; - arch/x86/entry/vdso, which isn't linked with KMSAN runtime; - three files in arch/x86/kernel - boot problems; - arch/x86/mm/cpu_entry_area.c - recursion. Signed-off-by: Alexander Potapenko --- v2: -- moved the patch earlier in the series so that KMSAN can compile -- split off the non-x86 part into a separate patch v3: -- added a comment to lib/Makefile Link: https://linux-review.googlesource.com/id/Id5e5c4a9f9d53c24a35ebb633b814c414628d81b --- arch/x86/boot/Makefile | 1 + arch/x86/boot/compressed/Makefile | 1 + arch/x86/entry/vdso/Makefile | 3 +++ arch/x86/kernel/Makefile | 2 ++ arch/x86/kernel/cpu/Makefile | 1 + arch/x86/mm/Makefile | 2 ++ arch/x86/realmode/rm/Makefile | 1 + lib/Makefile | 2 ++ 8 files changed, 13 insertions(+) diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile index b5aecb524a8aa..d5623232b763f 100644 --- a/arch/x86/boot/Makefile +++ b/arch/x86/boot/Makefile @@ -12,6 +12,7 @@ # Sanitizer runtimes are unavailable and cannot be linked for early boot code. KASAN_SANITIZE := n KCSAN_SANITIZE := n +KMSAN_SANITIZE := n OBJECT_FILES_NON_STANDARD := y # Kernel does not boot with kcov instrumentation here. diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index 19e1905dcbf6f..8d0d4d89a00ae 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -20,6 +20,7 @@ # Sanitizer runtimes are unavailable and cannot be linked for early boot code. KASAN_SANITIZE := n KCSAN_SANITIZE := n +KMSAN_SANITIZE := n OBJECT_FILES_NON_STANDARD := y # Prevents link failures: __sanitizer_cov_trace_pc() is not linked in. diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile index c2a8b76ae0bce..645bd919f9845 100644 --- a/arch/x86/entry/vdso/Makefile +++ b/arch/x86/entry/vdso/Makefile @@ -11,6 +11,9 @@ include $(srctree)/lib/vdso/Makefile # Sanitizer runtimes are unavailable and cannot be linked here. KASAN_SANITIZE := n +KMSAN_SANITIZE_vclock_gettime.o := n +KMSAN_SANITIZE_vgetcpu.o := n + UBSAN_SANITIZE := n KCSAN_SANITIZE := n OBJECT_FILES_NON_STANDARD := y diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 4c8b6ae802ac3..4f2617721d3dc 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -33,6 +33,8 @@ KASAN_SANITIZE_sev.o := n # With some compiler versions the generated code results in boot hangs, caused # by several compilation units. To be safe, disable all instrumentation. KCSAN_SANITIZE := n +KMSAN_SANITIZE_head$(BITS).o := n +KMSAN_SANITIZE_nmi.o := n OBJECT_FILES_NON_STANDARD_test_nx.o := y diff --git a/arch/x86/kernel/cpu/Makefile b/arch/x86/kernel/cpu/Makefile index 9661e3e802be5..f10a921ee7565 100644 --- a/arch/x86/kernel/cpu/Makefile +++ b/arch/x86/kernel/cpu/Makefile @@ -12,6 +12,7 @@ endif # If these files are instrumented, boot hangs during the first second. KCOV_INSTRUMENT_common.o := n KCOV_INSTRUMENT_perf_event.o := n +KMSAN_SANITIZE_common.o := n # As above, instrumenting secondary CPU boot code causes boot hangs. KCSAN_SANITIZE_common.o := n diff --git a/arch/x86/mm/Makefile b/arch/x86/mm/Makefile index f8220fd2c169a..39c0700c9955c 100644 --- a/arch/x86/mm/Makefile +++ b/arch/x86/mm/Makefile @@ -12,6 +12,8 @@ KASAN_SANITIZE_mem_encrypt_identity.o := n # Disable KCSAN entirely, because otherwise we get warnings that some functions # reference __initdata sections. KCSAN_SANITIZE := n +# Avoid recursion by not calling KMSAN hooks for CEA code. +KMSAN_SANITIZE_cpu_entry_area.o := n ifdef CONFIG_FUNCTION_TRACER CFLAGS_REMOVE_mem_encrypt.o = -pg diff --git a/arch/x86/realmode/rm/Makefile b/arch/x86/realmode/rm/Makefile index 83f1b6a56449f..f614009d3e4e2 100644 --- a/arch/x86/realmode/rm/Makefile +++ b/arch/x86/realmode/rm/Makefile @@ -10,6 +10,7 @@ # Sanitizer runtimes are unavailable and cannot be linked here. KASAN_SANITIZE := n KCSAN_SANITIZE := n +KMSAN_SANITIZE := n OBJECT_FILES_NON_STANDARD := y # Prevents link failures: __sanitizer_cov_trace_pc() is not linked in. diff --git a/lib/Makefile b/lib/Makefile index 5056769d00bb6..73fea85b76365 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -272,6 +272,8 @@ obj-$(CONFIG_POLYNOMIAL) += polynomial.o CFLAGS_stackdepot.o += -fno-builtin obj-$(CONFIG_STACKDEPOT) += stackdepot.o KASAN_SANITIZE_stackdepot.o := n +# In particular, instrumenting stackdepot.c with KMSAN will result in infinite +# recursion. KMSAN_SANITIZE_stackdepot.o := n KCOV_INSTRUMENT_stackdepot.o := n -- 2.37.0.rc0.161.g10f37bed90-goog