From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Frank Ch. Eigler" Subject: Re: [PATCH -tip v3 00/23] kprobes: introduce NOKPROBE_SYMBOL() and general cleaning of kprobe blacklist Date: Wed, 20 Nov 2013 12:36:00 -0500 Message-ID: <20131120173600.GK8993@redhat.com> References: <20131120042148.15296.88360.stgit@kbuild-fedora.novalocal> <20131120153801.GA9743@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mx1.redhat.com ([209.132.183.28]:21972 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751283Ab3KTRgW (ORCPT ); Wed, 20 Nov 2013 12:36:22 -0500 Content-Disposition: inline In-Reply-To: <20131120153801.GA9743@gmail.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Ingo Molnar Cc: Masami Hiramatsu , linux-arch@vger.kernel.org, Ananth N Mavinakayanahalli , Sandeepa Prabhu , x86@kernel.org, lkml , "Steven Rostedt (Red Hat)" , virtualization@lists.linux-foundation.org, systemtap@sourceware.org, "David S. Miller" Hi - > > Does this new blacklist cover enough that the kernel now survives a > > broadly wildcarded perf-probe, e.g. over e.g. all of its kallsyms? > > That's generally the purpose of the annotations - if it doesn't then > that's a bug. AFAIK, no kernel since kprobes was introduced has ever stood up to that test. perf probe lacks the wildcarding powers of systemtap, so one needs to resort to something like: # cat /proc/kallsyms | grep ' [tT] ' | while read addr type symbol; do perf probe $symbol done then wait for a few hours for that to finish. Then, or while the loop is still running, run # perf record -e 'probe:*' -aR sleep 1 to take a kernel down. - FChE