tree f42f4f732a2d7920009f34d798d1803def38ea44
parent cd649b8bb830d65c57c3c8b98d57b5402256d8bd
author Li Zefan <lizf@cn.fujitsu.com> 1237516440 +0800
committer Ingo Molnar <mingo@elte.hu> 1237648644 +0100

blktrace: avoid accessing NULL bdev->bd_disk

bdev->bd_disk can be NULL, if the block device is not opened.

Try this against an unmounted partition, and you'll see NULL dereference:

  # echo 1 > /sys/block/sda/sda5/enable

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <49C30098.6080107@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>