From patchwork Tue Oct 13 00:31:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834555 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8F5B992C for ; Tue, 13 Oct 2020 00:33:02 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id D78162173E for ; Tue, 13 Oct 2020 00:33:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="iWb8IMXO" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D78162173E Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20178-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 11877 invoked by uid 550); 13 Oct 2020 00:32:28 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 11711 invoked from network); 13 Oct 2020 00:32:26 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=oNoCiComLTOHVg2bP6STufgWA9yaYfJ6ObCLDl+jrho=; b=iWb8IMXO138pO3VxQeiLtRHBFKLEZX34wfy/I5tnQOY8tAz+5KN10zF+c5wKc0NGf9 V81W5t0kz8+T12z9fdWu+sNnGkAeOhHE8X9D+RroweYzMnASv3Hwpkndl/8bioQpHZUz mX+LtD994yaPGz2JhGYYCZ77UH77NBl51OSJVt2PNtGh/uJ/Id01J2GrYmku+3i3+EME 0RSLPnMFIoJMJWfen1rEiGkUdPfD4MN+VkmyC3f7ZHxJqifMISzpW0Ypub7BPOfBxhkE v+NEFC6Ds2T1GWHGqFR6HDQWg9+W5tlsLsaS1VukIHrqKwvMN5C/M7+MuFGvKKyjBneT I2Lw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=oNoCiComLTOHVg2bP6STufgWA9yaYfJ6ObCLDl+jrho=; b=uky5cxuMACEkCW1KAaeCcZnVq8m4aFH1rUBYY3DbnjDW+lNIwi81ZFtte9ovqnd+Qu t3iQiehVwBphs0TKuPjeDeZaYKvoCPsfSaX3U99OJzLiXDVU27uaPH716CylEsN0K0R0 tXz/A+8pJSUnGxUIcmtLMbUbiGs3rXullsdkf0g9r/MBEKF2FDu1x+4DhlRwykqscTQz xOPsmeg8maWpNJaGwCZB4O0lGueb+vksznsgxM0ZhfLbypRKH35zuAveOatwz9PfbcqZ nHzYLHlX31opG9j7sYy4cjbGRm6vPs2/0pvmZ1wbSpgJZFqlHSaPMf8qe6rfA/uI14zl uyNg== X-Gm-Message-State: AOAM533obWiY6o4LdPAx58bv2OhjUp5cSFD2zteW9jdVRZVqMXyFEswk 1giQZYi2aRBtp6XF5esVZfiRqh8m7GD74jWzlDs= X-Google-Smtp-Source: ABdhPJwwb1BOagS9KB2HJy67TJEwj+dNfREWLJyGXBWcLbfd0WCh9RIc4B6fwHPAmc6V1LYLv5oY+bdj39+DqlbHxJM= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:a25:a4e1:: with SMTP id g88mr11556641ybi.267.1602549135037; Mon, 12 Oct 2020 17:32:15 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:43 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-6-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 05/25] tracing: add support for objtool mcount From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen This change adds build support for using objtool to generate __mcount_loc sections. Signed-off-by: Sami Tolvanen --- Makefile | 12 ++++++++++-- kernel/trace/Kconfig | 13 +++++++++++++ scripts/Makefile.build | 3 +++ 3 files changed, 26 insertions(+), 2 deletions(-) diff --git a/Makefile b/Makefile index 129001b38357..fda1f8a0b1c7 100644 --- a/Makefile +++ b/Makefile @@ -850,6 +850,9 @@ ifdef CONFIG_FTRACE_MCOUNT_USE_CC endif endif endif +ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL + CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT +endif ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT ifdef CONFIG_HAVE_C_RECORDMCOUNT BUILD_C_RECORDMCOUNT := y @@ -1209,11 +1212,16 @@ uapi-asm-generic: PHONY += prepare-objtool prepare-resolve_btfids prepare-objtool: $(objtool_target) ifeq ($(SKIP_STACK_VALIDATION),1) +objtool-lib-prompt := "please install libelf-dev, libelf-devel or elfutils-libelf-devel" +ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL + @echo "error: Cannot generate __mcount_loc for CONFIG_DYNAMIC_FTRACE=y, $(objtool-lib-prompt)" >&2 + @false +endif ifdef CONFIG_UNWINDER_ORC - @echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2 + @echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, $(objtool-lib-prompt)" >&2 @false else - @echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2 + @echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, $(objtool-lib-prompt)" >&2 endif endif diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 927ad004888a..89263210ab26 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -51,6 +51,11 @@ config HAVE_NOP_MCOUNT help Arch supports the gcc options -pg with -mrecord-mcount and -nop-mcount +config HAVE_OBJTOOL_MCOUNT + bool + help + Arch supports objtool --mcount + config HAVE_C_RECORDMCOUNT bool help @@ -605,10 +610,18 @@ config FTRACE_MCOUNT_USE_CC depends on !FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY depends on FTRACE_MCOUNT_RECORD +config FTRACE_MCOUNT_USE_OBJTOOL + def_bool y + depends on HAVE_OBJTOOL_MCOUNT + depends on !FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY + depends on !FTRACE_MCOUNT_USE_CC + depends on FTRACE_MCOUNT_RECORD + config FTRACE_MCOUNT_USE_RECORDMCOUNT def_bool y depends on !FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY depends on !FTRACE_MCOUNT_USE_CC + depends on !FTRACE_MCOUNT_USE_OBJTOOL depends on FTRACE_MCOUNT_RECORD config TRACING_MAP diff --git a/scripts/Makefile.build b/scripts/Makefile.build index a4634aae1506..cd4294435fef 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -228,6 +228,9 @@ endif ifdef CONFIG_X86_SMAP objtool_args += --uaccess endif +ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL + objtool_args += --mcount +endif # 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory # 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file