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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 D4713C43A1D for ; Thu, 12 Jul 2018 00:40:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8E58A20BEC for ; Thu, 12 Jul 2018 00:40:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8E58A20BEC Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=efficios.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389695AbeGLArv convert rfc822-to-8bit (ORCPT ); Wed, 11 Jul 2018 20:47:51 -0400 Received: from mail-io0-f196.google.com ([209.85.223.196]:44473 "EHLO mail-io0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388683AbeGLAru (ORCPT ); Wed, 11 Jul 2018 20:47:50 -0400 Received: by mail-io0-f196.google.com with SMTP id q19-v6so26256757ioh.11 for ; Wed, 11 Jul 2018 17:40:56 -0700 (PDT) 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:content-transfer-encoding; bh=7iprcpX3pvTEdMCbDnh2jG3MsV7K+ssdsJkEDAGGItk=; b=QtD3PFIfZcIJYM8Zp0t0IMDgabYXETiuzMvxt9KASMye2TnHqktkBvXgLsLTq53n7G u4DhZP9yu609mUS5ol88+qa/npKHNJydM7UlTVqnzAfxsoCS699eDVFnDflG7sbxmYhf Z5OrOVqp/nDxd8LQB++zS4frYailPCmaBu2jBdyDfPYXdFMpB+x6k/tUelodiT2J4gev Othe4Jp44FWUn0VYsG/6IZ9yDib96qunlE//lRFnI7/MEp9SB1Ib/oU+Mkx5omAhSEoF J3g5xZdB4mzxyMFLL7y5o8cR4QprpNKrza7qpn8Scs8IgDDJtcCUbaPCMr5cn89hRoqv uHZA== X-Gm-Message-State: APt69E1QQkdXEe50N3tVrzuSOzET67ZQisTbz3CweW/tM/jLH2xSBUMA McO8fUhYPYHFJPRtHHxMsalN13O59bpNMweFY44= X-Google-Smtp-Source: AAOMgpfH8/l4LsMxanMpTmPyZ5eaPf/Hu27YeoInfplHVE1eAaywpqE1AMzeopzU2VBJOoJFHObIS3r/UnvUCwmfMWQ= X-Received: by 2002:a6b:8fd4:: with SMTP id r203-v6mr27134421iod.24.1531356056480; Wed, 11 Jul 2018 17:40:56 -0700 (PDT) MIME-Version: 1.0 References: <1500044315-9508-1-git-send-email-francis.deslauriers@efficios.com> <1500044315-9508-3-git-send-email-francis.deslauriers@efficios.com> <20170714142900.1c91949c@gandalf.local.home> <20180316112517.66bdd85a@gandalf.local.home> <229385456.11580.1521217739037.JavaMail.zimbra@efficios.com> <20180316124134.30fa47d5@gandalf.local.home> <20180316124840.3e83bbec@gandalf.local.home> <1577244734.11604.1521222781948.JavaMail.zimbra@efficios.com> <20180317091334.55f1fc325c26deaa4d4a4d19@kernel.org> <20180317102211.a648f26ae0d5a53d95c63022@kernel.org> <20180703183048.1eeeef4a@gandalf.local.home> <20180711155628.78b0fd83@gandalf.local.home> In-Reply-To: <20180711155628.78b0fd83@gandalf.local.home> From: Francis Deslauriers Date: Wed, 11 Jul 2018 20:40:45 -0400 Message-ID: Subject: Re: [PATCH 2/2] kprobe: fix: Add ftrace_ops_assist_func to kprobe blacklist To: Steven Rostedt Cc: Mathieu Desnoyers , Masami Hiramatsu , Peter Zijlstra , linux-kernel , torvalds@linux-foundation.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Le mer. 11 juill. 2018, à 15 h 56, Steven Rostedt a écrit : > > On Wed, 11 Jul 2018 15:34:30 -0400 > Francis Deslauriers wrote: > > > Hi Steven, > > I tested it and it prevents the kernel crash I am witnessing. > > As for the side-effect that Masami mentioned regarding not being able to probe > > function inside the trace_kprobe.c file, I suggest we move the target > > function in > > its own separate compile unit so it can be compiled with the ftrace cflags. > > See patch below. > > > > The patch below looks fine and so does Masami's. But there's too many > patches within emails (not separated out). I have no idea what to > apply. I'm not going to apply anything that is not sent as a proper > patch (ie. any patch within a separate thread, like the patch below). > I will put together a proper patch set with both commits. Masami, you mentioned: "So anyway we still need to mark those functions NOKPROBE_SYMBOL." in a reply. What functions were you talking about? ftrace_ops_assist_func? Aren't those functions covered by your within_notrace_func check? Thank you, Francis > -- Steve > > > > Thanks > > Francis > > > > >From d5a3645bd0046f28275d6b60207958f2751c1f47 Mon Sep 17 00:00:00 2001 > > From: Francis Deslauriers > > Date: Wed, 11 Jul 2018 12:34:22 -0400 > > Subject: [PATCH] selftest/ftrace: Move kprobe selftest function to separate > > compile unit > > > > Move selftest function to its own compile unit so it can be compiled > > with the ftrace cflags (CC_FLAGS_FTRACE) allowing it to be probed > > during the ftrace startup tests. > > > > Signed-off-by: Francis Deslauriers > > --- > > kernel/trace/Makefile | 5 +++++ > > kernel/trace/trace_kprobe.c | 12 +----------- > > kernel/trace/trace_kprobe_selftest.c | 10 ++++++++++ > > kernel/trace/trace_kprobe_selftest.h | 7 +++++++ > > 4 files changed, 23 insertions(+), 11 deletions(-) > > create mode 100644 kernel/trace/trace_kprobe_selftest.c > > create mode 100644 kernel/trace/trace_kprobe_selftest.h > > > > diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile > > index e2538c7..e38771e 100644 > > --- a/kernel/trace/Makefile > > +++ b/kernel/trace/Makefile > > @@ -13,6 +13,11 @@ obj-y += trace_selftest_dynamic.o > > endif > > endif > > > > +ifdef CONFIG_FTRACE_STARTUP_TEST > > +CFLAGS_trace_kprobe_selftest.o = $(CC_FLAGS_FTRACE) > > +obj-$(CONFIG_KPROBE_EVENTS) += trace_kprobe_selftest.o > > +endif > > + > > # If unlikely tracing is enabled, do not trace these files > > ifdef CONFIG_TRACING_BRANCHES > > KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING > > diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c > > index 952dc2a..3fe966f 100644 > > --- a/kernel/trace/trace_kprobe.c > > +++ b/kernel/trace/trace_kprobe.c > > @@ -24,6 +24,7 @@ > > #include > > > > #include "trace_probe.h" > > +#include "trace_kprobe_selftest.h" > > > > #define KPROBE_EVENT_SYSTEM "kprobes" > > #define KRETPROBE_MAXACTIVE_MAX 4096 > > @@ -1560,17 +1561,6 @@ fs_initcall(init_kprobe_trace); > > > > > > #ifdef CONFIG_FTRACE_STARTUP_TEST > > -/* > > - * The "__used" keeps gcc from removing the function symbol > > - * from the kallsyms table. 'noinline' makes sure that there > > - * isn't an inlined version used by the test method below > > - */ > > -static __used __init noinline int > > -kprobe_trace_selftest_target(int a1, int a2, int a3, int a4, int a5, int a6) > > -{ > > - return a1 + a2 + a3 + a4 + a5 + a6; > > -} > > - > > static __init struct trace_event_file * > > find_trace_probe_file(struct trace_kprobe *tk, struct trace_array *tr) > > { > > diff --git a/kernel/trace/trace_kprobe_selftest.c > > b/kernel/trace/trace_kprobe_selftest.c > > new file mode 100644 > > index 0000000..a3d2090 > > --- /dev/null > > +++ b/kernel/trace/trace_kprobe_selftest.c > > @@ -0,0 +1,10 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * Function used during the kprobe self test. This function is in a seperate > > + * compile unit so it can be compile with CC_FLAGS_FTRACE to ensure that it > > + * can be probed by the selftests. > > + */ > > +int kprobe_trace_selftest_target(int a1, int a2, int a3, int a4, int > > a5, int a6) > > +{ > > + return a1 + a2 + a3 + a4 + a5 + a6; > > +} > > diff --git a/kernel/trace/trace_kprobe_selftest.h > > b/kernel/trace/trace_kprobe_selftest.h > > new file mode 100644 > > index 0000000..9243d4e > > --- /dev/null > > +++ b/kernel/trace/trace_kprobe_selftest.h > > @@ -0,0 +1,7 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * Function used during the kprobe self test. This function is in a seperate > > + * compile unit so it can be compile with CC_FLAGS_FTRACE to ensure that it > > + * can be probed by the selftests. > > + */ > > +int kprobe_trace_selftest_target(int a1, int a2, int a3, int a4, int > > a5, int a6); > -- Francis Deslauriers Software developer EfficiOS inc.