Bug#689274: (almost 100% reproducible) kernel bug when trying to mount nfs filesystem

[Jonathan Nieder <jrnieder@gmail.com>]

tags 689274 = upstream fixed-upstream
quit

Hi Rogério,

Rogério Brito wrote:

> I have been semi-consistently (the almost 100% reproducible) getting a
> kernel Oops whenever I try to mount a NFS filesystem from another computer
> (an ARM, 32-bit NAS, running pure Debian armel unstable) from my network.
>
> This has only happened with kernel 3.5, but not with previous kernels.
[...]
> [ 9608.475559] kernel BUG at /build/buildd-linux_3.5.2-1~experimental.1-amd64-bLqIZ_/linux-3.5.2/fs/nfs/idmap.c:684!

This is the "BUG_ON(idmap->idmap_key_cons != NULL);"
discussed at http://thread.gmane.org/gmane.linux.nfs/51316/focus=1365689
The assertion was introduced in v3.5.1~32, so wheezy is not affected.

Could you try the attached patch, for example using instructions
from [1]?

Thanks for a pleasant report,
Jonathan

[1] http://kernel-handbook.alioth.debian.org/ch-common-tasks.html#s4.2.2