From patchwork Tue Sep 29 21:46:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11807103 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 E570F618 for ; Tue, 29 Sep 2020 21:48:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C490C20848 for ; Tue, 29 Sep 2020 21:48:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="dgV6SDo9" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728560AbgI2VsH (ORCPT ); Tue, 29 Sep 2020 17:48:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48194 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728530AbgI2Vqu (ORCPT ); Tue, 29 Sep 2020 17:46:50 -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 C567CC0613E2 for ; Tue, 29 Sep 2020 14:46:47 -0700 (PDT) Received: by mail-pg1-x54a.google.com with SMTP id e28so4090642pgm.15 for ; Tue, 29 Sep 2020 14:46:47 -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=19SL9ILYFnZ21fbCFqMg6UAhhhxZhQrjD+s35+X1B+w=; b=dgV6SDo9/nGgyVMUAcMHx0gvXIYyOXF6ty1/3uITkICbHspZeHQbvHxGwlJqzzv9XW 4V5LMwCn5zT2oQ8f4LzGfojh5OquEucov8kBAZlsAbKj8gS7+rq5Zf2MIFybCbJwmh+A b2F8LeTYsJjCidyUsKW6BDyg8O8Sinw+WaY1c0mDlAt5XShrnPVlrIVqksLlFRGU1Dp8 A8Bl7ulvb9diUaImQKfi6sNHBwVH8SiGCv69MXqgXzBQsCNHc9rP0hmPStj/ZcNkXD/B KaKtBNLUeB6r12MkOyu4JMGxpeLWC59hDNbjZmRjkjPVuauMgp1y6CR+/HcBDH41STN0 Kwbw== 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=19SL9ILYFnZ21fbCFqMg6UAhhhxZhQrjD+s35+X1B+w=; b=Q9Jb0sHnzbHRYo7NIIZF/YTom46JUao1z27uOIxY+cXrhRhEMav4LtENpxvqGBiQnC T43AUICSp+VcDdtKNjBNTd0guNlUT9GIWC4/RtrNjKrxZAY6fYiHcIyovcfyNhTcnmsG BduyUPZwzwMpdxXF0vujQNwRO5C5QQLjMBQ9Rjn3QYVT8lUCJoDoJ2ZAqsvD+gsvmED8 ESUggAcKcYFheb7uWxQM/x2K6zxLa/iNVSvPgHEXzIVKPhgMRbpPHFapDuyipfT8B+Sl RLZJDZJRpTE86OLEcSEECWGf9E+HOlRPliR5RBtPE+LIBQOWParN8O6cuLuz5/oNwp4x KoMw== X-Gm-Message-State: AOAM530h6LvWZlIST5KDooUGBRsXMuwW4Z3MwViLC9ziZatPqRqZD2bZ /zmx4PWVBnomfOs0doOED/BxWSZ+WHANWCA+b6A= X-Google-Smtp-Source: ABdhPJx1IWNK7mnxuP/Nk+1pT7lWQ22j29Zw+7lY5TtajrC4ZWI/DVx3Sv0QEYCQpGeJUBhPmBSAfh824OrxIAP+HiE= 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:a17:90a:c907:: with SMTP id v7mr5593265pjt.204.1601416007270; Tue, 29 Sep 2020 14:46:47 -0700 (PDT) Date: Tue, 29 Sep 2020 14:46:09 -0700 In-Reply-To: <20200929214631.3516445-1-samitolvanen@google.com> Message-Id: <20200929214631.3516445-8-samitolvanen@google.com> Mime-Version: 1.0 References: <20200929214631.3516445-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.709.gb0816b6eb0-goog Subject: [PATCH v4 07/29] 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 77e4f0a9495e..9717005e41c4 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