linux-kernel - perf TUI fails with "failed to process type: 64"

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Sun, 9 Oct 2016 12:12:32 +1100
From:   Anton Blanchard <anton@...ba.org>
To:     Michael Ellerman <mpe@...erman.id.au>,
        Benjamin Herrenschmidt <benh@...nel.crashing.org>,
        Paul Mackerras <paulus@...ba.org>,
        Nicholas Piggin <npiggin@...il.com>,
        ravi.bangoria@...ux.vnet.ibm.com, acme@...hat.com,
        peterz@...radead.org, mingo@...hat.com,
        alexander.shishkin@...ux.intel.com
Cc:     linux-kernel@...r.kernel.org, linuxppc-dev@...ts.ozlabs.orgp
Subject: perf TUI fails with "failed to process type: 64"

Hi,

Updating to mainline as of last night, I started seeing the following
error when running the perf report TUI:

0x46068 [0x8]: failed to process type: 68

This event is just PERF_RECORD_FINISHED_ROUND:

0x46068 [0x8]: event: 68
.
. ... raw event: size 8 bytes
.  0000:  44 00 00 00 00 00 08 00                          D.......        

0x46068 [0x8]: PERF_RECORD_FINISHED_ROUND

Which of course is not our error. It took me a while to find the real
culprit:

 14c00-14c00 g exc_virt_0x4c00_system_call

A zero length symbol, which __symbol__inc_addr_samples() barfs on:

        if (addr < sym->start || addr >= sym->end) {
...
		return -ERANGE;

Seems like we have 3 bugs here:

1. Output the real source of the error instead of PERF_RECORD_FINISHED_ROUND

2. Don't exit the TUI if we find a sample on a zero length symbol

3. Why do we have zero length symbols in the first place? Does the recent
   ppc64 exception clean up have something to do with it?

Anton