From patchwork Fri Oct 9 16:13:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11826599 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 442DD139F for ; Fri, 9 Oct 2020 16:16:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2304622261 for ; Fri, 9 Oct 2020 16:16:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="h0+iMSN9" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389691AbgJIQP6 (ORCPT ); Fri, 9 Oct 2020 12:15:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41500 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389649AbgJIQNx (ORCPT ); Fri, 9 Oct 2020 12:13:53 -0400 Received: from mail-pg1-x54a.google.com (mail-pg1-x54a.google.com [IPv6:2607:f8b0:4864:20::54a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1C013C0613D7 for ; Fri, 9 Oct 2020 09:13:52 -0700 (PDT) Received: by mail-pg1-x54a.google.com with SMTP id s4so6974648pgk.17 for ; Fri, 09 Oct 2020 09:13:52 -0700 (PDT) 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=fZ3RySPWXLEyLlwdfUBpRpGrz5rbV/kevtEX3k0sv+Y=; b=h0+iMSN91xyn7Dij5lJ5UbfgKe5O3aXq0nghcYk8xVnglIOCrQqxOVA8AUxH1ox9lY S643yCM1/EupRGz2gOHgxQ/5gvY/herznEKaLgVjp1sIBiDgFItKoMQtTvQvf2UU/zqV 5ztVLJloZBfDrTzUMvL5OeXrDhFdMnPJ4FhTwo35ts/tnx/zpGiS8axwHCdHChiAsy5u YA3wPTak4Usradm7+BsNh1Hj45M6+dloyt70hARr+Abgvw4m8BW58l6uHGxwH+KxmDG8 kcIGcr+ag1qz/bDFIAXEhS+n1UiFqbFQj74/EllM5dvSE2qM7vf+EsUuLM6wi2vT8Gc2 syxg== 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=fZ3RySPWXLEyLlwdfUBpRpGrz5rbV/kevtEX3k0sv+Y=; b=cm40k20tDWMRdq0VC52y8HAZegrWQCv1ZIrGs2GfpFhI+5rR+cZR0e7GGBam0ECHMh UNFL0zqEz1EKt56/so0ibPSUPGlICO81ZoTp1jmpZwi+Vals3ZPTO9V/adcIbpIwT6aX 5fsE5W/ufaiDPz4lWu9h03rTAi5YSwlhpYg5p/uA6l5o8bR3qnLlo0ZYgK6pF14UDk0i ShCtio/BxE8RaLIf4LNchnk6s9dW7dh02JfykEOFzs4nQDuz0EU9edqSsDXxz9zGbBdU uGSZMi8UDDc8mjtFG12SDH3iS/ZdpbgLMaw5P9mqyJGexBx20fHUED26TSki72gcpcC3 ha7A== X-Gm-Message-State: AOAM53378GUG+BVn0AqYWKM2aIg4Fz+1rEnq8nlh98cs0yr9O4ix/o+k I9Vr2hVl2J6XL9+ZfqkM87bxKYosNRWxq9EtfV4= X-Google-Smtp-Source: ABdhPJyc4blDzdYkWSMfGJdy/E9dbY7N6G3wThrVqnkIlxKSMtyHPwEItcmQswW4Ja4IB9mj/wYhj+U071oOqaOsOz0= 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:a63:160b:: with SMTP id w11mr3996703pgl.110.1602260031610; Fri, 09 Oct 2020 09:13:51 -0700 (PDT) Date: Fri, 9 Oct 2020 09:13:14 -0700 In-Reply-To: <20201009161338.657380-1-samitolvanen@google.com> Message-Id: <20201009161338.657380-6-samitolvanen@google.com> Mime-Version: 1.0 References: <20201009161338.657380-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v5 05/29] tracing: add support for objtool mcount From: Sami Tolvanen To: Masahiro Yamada , Will Deacon , Steven Rostedt Cc: 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 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org This change adds build support for using objtool to generate __mcount_loc sections. Signed-off-by: Sami Tolvanen --- Makefile | 12 ++++++++++-- kernel/trace/Kconfig | 13 +++++++++++++ 2 files changed, 23 insertions(+), 2 deletions(-) diff --git a/Makefile b/Makefile index 434da9fcbf3c..fb2cf557d3ca 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