[Expired for linux (Ubuntu) because there has been no activity for 60
days.]
** Changed in: linux (Ubuntu)
Status: Incomplete => Expired
--
You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux in Ubuntu.
https://bugs.launchpad.net/bugs/1559563
Title:
Kernel Oops - unable to handle kernel paging request at
fffffffffffffff8; EIP is at gss_wrap_req_priv.isra.10+0x183/0x2d0
Status in linux package in Ubuntu:
Expired
Bug description:
This is a kernel oops that appears to occur under heavy load.
Unfortunately, it is not easy to reproduce, and I haven't been able to
isolate whether it's associated with NFS load, CPU load, both, or
neither. (NFS appears to be relevant, I'm using NFS4 with Kerberos in
krb5p, and the oops is in GSS code. I am not using Kerberos for login
or other features.)
The oops output is attached. Nothing occurs in the console output for
hours before it, and I suspect the second oops is related to the first
one in some way. Shortly afterward, soft lockups on all other cores
(including those on a physically separate processor) make the computer
unresponsive.
The issue appears to be in net/sunrpc/auth_gss/auth_gss.c's
gss_wrap_req_priv, in the following line:
tmp = page_address(rqstp->rq_enc_pages[rqstp->rq_enc_pages_num - 1]);
It appears that rqstp is set, but both rqstp->rq_enc_Pages and
rqstp->rq_enc_pages_num are zero, leading the kernel to attempt
dereferencing an invalid address. Because this surfaces only under
load, and is on a multiple-processor system, I'm inclined to guess
there is a race condition between accesses to rqstp on different
cores, but I haven't been able to determine where at this point.
Unfortunately, /proc/version_signature isn't currently available as
the computer got updated to a 3.13.0-77-generic upon restart, but this
was running on a stock "3.13.0-76-generic #120-Ubuntu" kernel on
14.04/trusty.
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1559563/+subscriptions
--
Mailing list: https://launchpad.net/~kernel-packages
Post to : kernel-packages@lists.launchpad.net
Unsubscribe : https://launchpad.net/~kernel-packages
More help : https://help.launchpad.net/ListHelp
