On Wed, Feb 4, 2015 at 8:10 AM, James Cameron <qu...@laptop.org> wrote: > Following up a thread from last September. > > This problem has just become more interesting, because it hit during > an activity startup. > > I'm quite used to seeing it with yum. But seeing it without yum now > points us at kernel, glibc or python.
We've not seen this in the wider F-20 Fedora ARM distro so my bet would be on the kernel. Peter > http://dev.laptop.org/ticket/12837#comment:4 has the details of the > most recent event. > > On Wed, Sep 10, 2014 at 01:56:27PM +1000, James Cameron wrote: >> G'day Peter, >> >> Thanks for any ideas you may have. >> >> The problem also reproduces on OLPC Fedora 20 image for XO-4: >> >> http://build.laptop.org/14.1.0/os1/xo-4/41001o4.zd (552 MB) >> >> *** Error in `/usr/bin/python': free(): invalid pointer: 0x047c79ae *** >> ======= Backtrace: ========= >> /lib/libc.so.6(+0x6c8b4)[0xb6c828b4] >> /lib/libc.so.6(+0x754e8)[0xb6c8b4e8] >> ======= Memory map: ======== >> [...] >> >> The error varies in detail, but always suggests corruption of heap or >> pointers to heap. >> >> The triggering conditions are interactive use of yum, yum update, or >> yum used by olpc-os-builder. The latter is a simple reproducer for me. >> >> I'm reproducing it on an XO-4, with 2GB of RAM, no swap, 8 GB eMMC, 8 >> GB USB flash drive. >> >> While memory demand by yum is large by comparison to other programs, >> the available memory at the time of failure is ample. There are no >> kernel out of memory (OOM) events. It seems more likely to occur when >> the filesystem cache is under heavy demand. >> >> The method to recreate the problem was: >> >> 1. install the system image 41001o4.zd using fs-update and then boot, >> >> 2. configure wireless network, >> >> 3. "yum install -y git olpc-os-builder" >> >> 4. clone the master branch of >> git://dev.laptop.org/projects/olpc-os-builder >> (last verified with b87e6ee) >> >> 5. run "./osbuilder.py examples/olpc-os-14.1.0-xo4.ini" repeatedly >> until the error occurs (usually within about five attempts), >> >> >> I've also tried running under valgrind, but that causes illegal >> instruction. It is quite likely I'm not using valgrind correctly. >> http://dev.laptop.org/~quozl/z/1XRYtO.txt >> >> The workaround at the moment is to build our Fedora 20 images on >> Fedora 18. Fedora 18 shows no sign of the problem. I'm worried that >> a low probability heap corruptor may cause instability of applications >> in the field. >> >> The exact same kernel is being used for Fedora 18 and Fedora 20. >> >> On Tue, Sep 09, 2014 at 03:55:24PM +0100, Peter Robinson wrote: >> > What version of OOB are you using, and what config files? I can try >> > and recreate the problem here on other devices. >> >> -- >> James Cameron >> http://quozl.linux.org.au/ > > -- > James Cameron > http://quozl.linux.org.au/ _______________________________________________ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
