Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754217AbcKOWOy (ORCPT ); Tue, 15 Nov 2016 17:14:54 -0500 Received: from mail-wm0-f50.google.com ([74.125.82.50]:36004 "EHLO mail-wm0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752445AbcKOWOw (ORCPT ); Tue, 15 Nov 2016 17:14:52 -0500 MIME-Version: 1.0 In-Reply-To: References: <1478902913-143778-1-git-send-email-keescook@chromium.org> From: Kees Cook Date: Tue, 15 Nov 2016 14:14:49 -0800 X-Google-Sender-Auth: 0AnESxOc4a-bHbzZZrkP8HUi9OQ Message-ID: Subject: Re: [PATCH v3 0/8] pstore: Improve performance of ftrace backend with ramoops To: Joel Fernandes Cc: Anton Vorontsov , Colin Cross , Tony Luck , LKML Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1582 Lines: 45 On Tue, Nov 15, 2016 at 2:06 PM, Joel Fernandes wrote: > Hi Kees, > > On Tue, Nov 15, 2016 at 1:36 PM, Kees Cook wrote: >> On Tue, Nov 15, 2016 at 11:55 AM, Joel Fernandes wrote: >>> Hi Kees, >>> >>> On Fri, Nov 11, 2016 at 2:21 PM, Kees Cook wrote: >>>> Hi Joel, >>>> >>>> I've reorganized a bunch of the logic here. Since pstore is going to need >>>> the init_przs() logic for multiple pmsg przs, I wanted to get this in and >>>> make sure I was happy with how it looks. I figured this would reduce our >>>> round-trip time on reviews. :) >>>> >>>> Can you test this series and verify that it works as you're expecting? I've >>>> validated some basic behavior already, but don't have a good test-case for >>>> ftrace. What commands do you actually use for testing ftrace? I'd like to >>>> add something to my local tests. >>> >>> I normally do the following: >>> >>> dd if=/dev/urandom | pv | dd of=/dev/null >>> >>> and in parallel, I do a: >>> echo 1 > /sys/kernel/debug/pstore/record_ftrace >>> >>> and then check the throughput; and then reboot the system and do a >>> read out of /sys/fs/pstore/ ftrace file. >> >> Cool. Does something normally parse these? Lots of kernel addresses is >> all I see. ;) >> > > It should print symbol names if KALLSYMS is working properly as it > uses %pf (in pstore_ftrace_seq_show function). Hrm. No such luck for me, but it's clearly using pstore correctly, so I'm satisfied things are working along that path. :) -Kees -- Kees Cook Nexus Security