linux-perf-users.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Milian Wolff <milian.wolff@kdab.com>
To: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: linux-perf-users@vger.kernel.org
Subject: Re: perf trace: Problems initializing symbol libraries!
Date: Mon, 16 May 2016 13:31:48 +0200	[thread overview]
Message-ID: <1849423.FYp0BrzLMo@agathebauer> (raw)
In-Reply-To: <20160512181044.GK20258@kernel.org>

[-- Attachment #1: Type: text/plain, Size: 1435 bytes --]

On Donnerstag, 12. Mai 2016 15:10:44 CEST Arnaldo Carvalho de Melo wrote:
> Em Thu, May 12, 2016 at 02:05:35PM +0200, Milian Wolff escreveu:
> > I'm getting the following error when trying to run `perf trace` built from
> > acme's perf/core branch on an Ubuntu 16.04 machine:
> > 
> > $ perf trace
> > Problems initializing symbol libraries!
> > 
> > strace shows this at the end:
> > 
> > ...
> > lstat("/proc", {st_mode=S_IFDIR|0555, st_size=0, ...}) = 0
> > lstat("/proc/kallsyms", {st_mode=S_IFREG|0444, st_size=0, ...}) = 0
> > write(2, "Problems initializing symbol lib"..., 40Problems initializing
> > symbol libraries!
> > ) = 40
> > exit_group(244)
> > 
> > Is something wrong with my /proc/kallsyms? Can someone tell me what the
> > problems are that are being encountered?
> 
> Does it work as root?

It does work as root. Note that on my other machines, I can run these commands 
to make it work as a non-root user:

sudo mount -o remount,mode=755 /sys/kernel/debug
sudo mount -o remount,mode=755 /sys/kernel/debug/tracing
echo "-1" | sudo tee /proc/sys/kernel/perf_event_paranoid

This does not work on Ubuntu 16.04 anymore.

> 
> What is the value of /proc/sys/kernel/kptr_restrict?
> 

This file does not exist.

> Need to improve that message :-\

Yes please :)

-- 
Milian Wolff | milian.wolff@kdab.com | Software Engineer
KDAB (Deutschland) GmbH&Co KG, a KDAB Group company
Tel: +49-30-521325470
KDAB - The Qt Experts

[-- Attachment #2: smime.p7s --]
[-- Type: application/pkcs7-signature, Size: 5903 bytes --]

  reply	other threads:[~2016-05-16 11:31 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-05-12 12:05 perf trace: Problems initializing symbol libraries! Milian Wolff
2016-05-12 18:10 ` Arnaldo Carvalho de Melo
2016-05-16 11:31   ` Milian Wolff [this message]
2016-05-16 13:15     ` Arnaldo Carvalho de Melo
2016-05-16 20:13     ` Arnaldo Carvalho de Melo
2016-05-17  7:51       ` Milian Wolff
2016-05-17 15:06         ` Arnaldo Carvalho de Melo
2016-05-23 10:05           ` Milian Wolff

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1849423.FYp0BrzLMo@agathebauer \
    --to=milian.wolff@kdab.com \
    --cc=acme@kernel.org \
    --cc=linux-perf-users@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).