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 X-Spam-Level: X-Spam-Status: No, score=-12.1 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_IN_DEF_DKIM_WL autolearn=no 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 F241CC4727C for ; Wed, 30 Sep 2020 16:06:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A175E2087D for ; Wed, 30 Sep 2020 16:06:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="FdREMa9Y" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731171AbgI3QGA (ORCPT ); Wed, 30 Sep 2020 12:06:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47984 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731099AbgI3QFv (ORCPT ); Wed, 30 Sep 2020 12:05:51 -0400 Received: from mail-ej1-x641.google.com (mail-ej1-x641.google.com [IPv6:2a00:1450:4864:20::641]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 25E85C0613D2 for ; Wed, 30 Sep 2020 09:05:51 -0700 (PDT) Received: by mail-ej1-x641.google.com with SMTP id a3so2826647ejy.11 for ; Wed, 30 Sep 2020 09:05:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=4nf8e6hIaPbRqntvQjCiPI17gKDQL3g6MdR3siKHn30=; b=FdREMa9YQ4gNRdQHURf/x/R8SmYVJ5gIkH9KpmlqeEAlOLeXAhaYjSC7VB4Y8/uoLl NpSU9flOBZMB2LnlrWowvIpCnct6WksL48hJ6hEvbeije9viNCjBJLNglsVPmK17McTE bQR932o1ftCv5I/jccydLYq37ELOk8HLaS5waUMw2Sl4+mDrlXBlbynVNtazEd8rcTZn oCfVkT2gQBFoWgRMv35xCS9XqXQ6DAZwYypy9P5mdyuszGukdvxnnn/AnzhUUV4OJTG3 jalYoYIzQjQOW6W2UeOKJ1wH4ANi3gdiXC8IiXeG+7KUsH9D9cVc5b9Ynx38GiIxo6v5 fQpQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=4nf8e6hIaPbRqntvQjCiPI17gKDQL3g6MdR3siKHn30=; b=BT9Dlaj8XHDExcTH9ezldtAP7Rp81atSNxViVM4Dv7H64jT3Zc6BTXmwbLy8NtOTJE 4SDgoLuq77avNzwOPrc+ulF+rPsXizQ4l5FkVIEBnc0i9Gawzg2hMh2fHDJ9Us9RuPTC AtuKsWflsktlltqTI38nXz2/sthDTVXYb/m+hFzDvuFAXS1rdVGdbdsYrWoKmKV/g5+W sjj9Jkbj/a5GY3Q5EwpJQADP7at6bI5+mF1l3YvlHNpiDbE6XC/TPzeMYdN3WzvWOlH2 mTQlsZhN8VE3hzKqEikB61XZJiicKW6nGpcUEmQdLpuYFQpW0M0qrP5e8qFrtHBG+ec+ 8OFA== X-Gm-Message-State: AOAM530XCHfHyeb8Dv0IGRhjtTQqZjzn6hz2vwdCHs13KHs1rXrrTCem PFEm9m1Qhcd6exM4X5hiWsyO7HApDfFET6Jkk4dHpg== X-Google-Smtp-Source: ABdhPJzYVdbm3fjbvWcAsssxdkKlp1Qf8hBl3VmZLS0706h18aYEVSeaUqFy3XkT6TY1fv56XT82VdDVYI9SZJ5H+mA= X-Received: by 2002:a17:906:a256:: with SMTP id bi22mr3464394ejb.375.1601481949457; Wed, 30 Sep 2020 09:05:49 -0700 (PDT) MIME-Version: 1.0 References: <20200929214631.3516445-1-samitolvanen@google.com> <20200929214631.3516445-7-samitolvanen@google.com> <20200929201257.1570aadd@oasis.local.home> In-Reply-To: <20200929201257.1570aadd@oasis.local.home> From: Sami Tolvanen Date: Wed, 30 Sep 2020 09:05:38 -0700 Message-ID: Subject: Re: [PATCH v4 06/29] tracing: move function tracer options to Kconfig To: Steven Rostedt Cc: Masahiro Yamada , Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux , Kernel Hardening , linux-arch , linux-arm-kernel , linux-kbuild , LKML , linux-pci@vger.kernel.org, X86 ML Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 29, 2020 at 5:13 PM Steven Rostedt wrote: > > On Tue, 29 Sep 2020 14:46:08 -0700 > Sami Tolvanen wrote: > > > +++ b/kernel/trace/Kconfig > > @@ -595,6 +595,22 @@ config FTRACE_MCOUNT_RECORD > > depends on DYNAMIC_FTRACE > > depends on HAVE_FTRACE_MCOUNT_RECORD > > > > +config FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY > > + bool > > + depends on FTRACE_MCOUNT_RECORD > > + > > +config FTRACE_MCOUNT_USE_CC > > + def_bool y > > + depends on $(cc-option,-mrecord-mcount) > > Does the above get executed at every build? Or does a make *config need > to be done? If someone were to pass a .config to someone else that had > a compiler that didn't support this, would it be changed if the person > just did a make? Yes, it's updated if you copy a .config and just run make. For example, here's what happens when I create a config with gcc and then build it with Clang: $ make defconfig ... $ ./scripts/config -e FUNCTION_TRACER -e DYNAMIC_FTRACE $ make olddefconfig ... $ grep MCOUNT_USE .config CONFIG_FTRACE_MCOUNT_USE_CC=y $ make CC=clang scripts/kconfig/conf --syncconfig Kconfig ... ^C $ grep MCOUNT_USE .config CONFIG_FTRACE_MCOUNT_USE_OBJTOOL=y Sami 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 X-Spam-Level: X-Spam-Status: No, score=-4.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_ADSP_CUSTOM_MED,DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 0BE0CC4727C for ; Wed, 30 Sep 2020 16:07:50 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8777D20789 for ; 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Wed, 30 Sep 2020 09:05:49 -0700 (PDT) MIME-Version: 1.0 References: <20200929214631.3516445-1-samitolvanen@google.com> <20200929214631.3516445-7-samitolvanen@google.com> <20200929201257.1570aadd@oasis.local.home> In-Reply-To: <20200929201257.1570aadd@oasis.local.home> From: Sami Tolvanen Date: Wed, 30 Sep 2020 09:05:38 -0700 Message-ID: Subject: Re: [PATCH v4 06/29] tracing: move function tracer options to Kconfig To: Steven Rostedt X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200930_120553_760170_05598201 X-CRM114-Status: GOOD ( 17.96 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch , X86 ML , Kees Cook , "Paul E. McKenney" , Kernel Hardening , Peter Zijlstra , Greg Kroah-Hartman , Masahiro Yamada , linux-kbuild , Nick Desaulniers , LKML , clang-built-linux , linux-pci@vger.kernel.org, Will Deacon , linux-arm-kernel Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Sep 29, 2020 at 5:13 PM Steven Rostedt wrote: > > On Tue, 29 Sep 2020 14:46:08 -0700 > Sami Tolvanen wrote: > > > +++ b/kernel/trace/Kconfig > > @@ -595,6 +595,22 @@ config FTRACE_MCOUNT_RECORD > > depends on DYNAMIC_FTRACE > > depends on HAVE_FTRACE_MCOUNT_RECORD > > > > +config FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY > > + bool > > + depends on FTRACE_MCOUNT_RECORD > > + > > +config FTRACE_MCOUNT_USE_CC > > + def_bool y > > + depends on $(cc-option,-mrecord-mcount) > > Does the above get executed at every build? Or does a make *config need > to be done? If someone were to pass a .config to someone else that had > a compiler that didn't support this, would it be changed if the person > just did a make? Yes, it's updated if you copy a .config and just run make. For example, here's what happens when I create a config with gcc and then build it with Clang: $ make defconfig ... $ ./scripts/config -e FUNCTION_TRACER -e DYNAMIC_FTRACE $ make olddefconfig ... $ grep MCOUNT_USE .config CONFIG_FTRACE_MCOUNT_USE_CC=y $ make CC=clang scripts/kconfig/conf --syncconfig Kconfig ... ^C $ grep MCOUNT_USE .config CONFIG_FTRACE_MCOUNT_USE_OBJTOOL=y Sami _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel 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 X-Spam-Level: X-Spam-Status: No, score=-12.1 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_IN_DEF_DKIM_WL autolearn=no 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 4579AC47420 for ; Wed, 30 Sep 2020 16:06:10 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 3535B2087D for ; Wed, 30 Sep 2020 16:06:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="FdREMa9Y" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3535B2087D 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-20068-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 26400 invoked by uid 550); 30 Sep 2020 16:06:01 -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: Received: (qmail 26365 invoked from network); 30 Sep 2020 16:06:01 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=4nf8e6hIaPbRqntvQjCiPI17gKDQL3g6MdR3siKHn30=; b=FdREMa9YQ4gNRdQHURf/x/R8SmYVJ5gIkH9KpmlqeEAlOLeXAhaYjSC7VB4Y8/uoLl NpSU9flOBZMB2LnlrWowvIpCnct6WksL48hJ6hEvbeije9viNCjBJLNglsVPmK17McTE bQR932o1ftCv5I/jccydLYq37ELOk8HLaS5waUMw2Sl4+mDrlXBlbynVNtazEd8rcTZn oCfVkT2gQBFoWgRMv35xCS9XqXQ6DAZwYypy9P5mdyuszGukdvxnnn/AnzhUUV4OJTG3 jalYoYIzQjQOW6W2UeOKJ1wH4ANi3gdiXC8IiXeG+7KUsH9D9cVc5b9Ynx38GiIxo6v5 fQpQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=4nf8e6hIaPbRqntvQjCiPI17gKDQL3g6MdR3siKHn30=; b=Kdcz816JHH5luyFY6Gc9yztfH/jLrlj+hXpgt8z4PmtWg0bbW7H/CV7ud+0NJarO3y 5SzU0jVBnJJIYpgcEuKD7fgkgcnLvb/gQ9aEzgmfNymXhow5JKzsYWXiFL0l9GAnpEmx gUrGfOfV+VXgY90HZAYyNhCxEp/Zeyh7bu84UVRD82g/ZNBzHKSfCSrkl9ESCm+/dNe9 gys36uIBTIJMxX+mJAI2rPpm8sWH3ICKqukW/vSw3Xsq7uXYlf6Qbw0ABDEq4TclZXg6 2s3O5tQDCVWIvjJS1hA/3BZdAxGS6H66z1fgjfkj4aMPi+XoaFTrgpz9EmYDm39H2qTG +bow== X-Gm-Message-State: AOAM532mSUiCx6ZMu2H8/mNsHt27s1dt6DWAp7owYnNjGlIhvIIj9NHJ WUk5+tFw+c01uOvAaTPXPr0k12fb5eJn6VmNVhfx+w== X-Google-Smtp-Source: ABdhPJzYVdbm3fjbvWcAsssxdkKlp1Qf8hBl3VmZLS0706h18aYEVSeaUqFy3XkT6TY1fv56XT82VdDVYI9SZJ5H+mA= X-Received: by 2002:a17:906:a256:: with SMTP id bi22mr3464394ejb.375.1601481949457; Wed, 30 Sep 2020 09:05:49 -0700 (PDT) MIME-Version: 1.0 References: <20200929214631.3516445-1-samitolvanen@google.com> <20200929214631.3516445-7-samitolvanen@google.com> <20200929201257.1570aadd@oasis.local.home> In-Reply-To: <20200929201257.1570aadd@oasis.local.home> From: Sami Tolvanen Date: Wed, 30 Sep 2020 09:05:38 -0700 Message-ID: Subject: Re: [PATCH v4 06/29] tracing: move function tracer options to Kconfig To: Steven Rostedt Cc: Masahiro Yamada , Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux , Kernel Hardening , linux-arch , linux-arm-kernel , linux-kbuild , LKML , linux-pci@vger.kernel.org, X86 ML Content-Type: text/plain; charset="UTF-8" On Tue, Sep 29, 2020 at 5:13 PM Steven Rostedt wrote: > > On Tue, 29 Sep 2020 14:46:08 -0700 > Sami Tolvanen wrote: > > > +++ b/kernel/trace/Kconfig > > @@ -595,6 +595,22 @@ config FTRACE_MCOUNT_RECORD > > depends on DYNAMIC_FTRACE > > depends on HAVE_FTRACE_MCOUNT_RECORD > > > > +config FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY > > + bool > > + depends on FTRACE_MCOUNT_RECORD > > + > > +config FTRACE_MCOUNT_USE_CC > > + def_bool y > > + depends on $(cc-option,-mrecord-mcount) > > Does the above get executed at every build? Or does a make *config need > to be done? If someone were to pass a .config to someone else that had > a compiler that didn't support this, would it be changed if the person > just did a make? Yes, it's updated if you copy a .config and just run make. For example, here's what happens when I create a config with gcc and then build it with Clang: $ make defconfig ... $ ./scripts/config -e FUNCTION_TRACER -e DYNAMIC_FTRACE $ make olddefconfig ... $ grep MCOUNT_USE .config CONFIG_FTRACE_MCOUNT_USE_CC=y $ make CC=clang scripts/kconfig/conf --syncconfig Kconfig ... ^C $ grep MCOUNT_USE .config CONFIG_FTRACE_MCOUNT_USE_OBJTOOL=y Sami