In 2.6.31, sysfs exposes the request queue of block drivers that don't use a request queue. The aoe driver was not allocating its request queue using the block layer's functions like blk_alloc_queue or blk_init_queue, and so an oops was being generated.
This patch uses blk_alloc_queue to allocate the queue in the expected way. Jens Axboe says that the aoe driver should have been doing that already, even though the recent changes to the kobject code revealed the problem.
This patch is now (20090910) being pushed from Jens Axboe to Linus Torvalds.