tree edbe103c6c5c2fe971ee270d8b0e3ae7dab8af83
parent cd52d1ee9a92587b242d946a2300a3245d3b885a
author Zachary Amsden <zach@vmware.com> 1131538981 +0100
committer Jens Axboe <axboe@nelson.home.kernel.dk> 1131789288 +0100

[BLOCK] elevator init fixes

I got a panic in the elevator code, backtrace :

Unable to handle kernel NULL pointer dereference at virtual address 00000060
..
EIP is at elevator_put+0x0/0x30 (null elevator_type passed)
..
elevator_init+0x38
blk_init_queu_node+0xc9
floppy_init+0xdb
do_initcalls+0x23
init+0x10a
init+0x0

Clearly if the kmalloc here fails, e->elevator_type is not yet set; this
appears to be the correct fix, but I think I probably hit the second case
due to a race condition.  Someone more familiar with the elevator code
should look at this more closely until I can determine if I can reproduce.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jens Axboe <axboe@suse.de>