Oops on blktrace

Hello,

I just experienced an Oops while running blktrace on a 2.6.30.9 kernel (production system). There was no camera handy and no serial console or crash dump log, so all we could get remotely was a function backtrace copied by hand:

memset_c
relay_open_buf
relay_open
do_blk_trace_setup
blk_trace_setup
disk_name | HEX/HEX
blk_trace_ioctl
find_get_page
blkdev_ioctrl
filemap_fault
unlock_page
__do_fault
block_ioctl
vfs_ioctl
do_vfs_ioctl
sys_ioctl
system_call_fastpath

At the time I had just run "blktrace /dev/etherd/e10.1" (an AOE device), having recently run "btrace -t /dev/etherd/e10.1" and similar with no problem. I've since tried to reproduce this crash to no avail. Have there been any similar experiences or related fixes since 2.6.30.9?

Cheers,

Simon-