tree 2bf7586a979548fb0fc950e5b84b646f96360ea6
parent d4a4f75cd8f29cd9464a5a32e9224a91571d6649
author Ming Lei <tom.leiming@gmail.com> 1433427904 +0800
committer Jens Axboe <axboe@fb.com> 1433885558 -0600

blk-mq: free hctx->ctxs in queue's release handler

Now blk_cleanup_queue() can be called before calling
del_gendisk()[1], inside which hctx->ctxs is touched
from blk_mq_unregister_hctx(), but the variable has
been freed by blk_cleanup_queue() at that time.

So this patch moves freeing of hctx->ctxs into queue's
release handler for fixing the oops reported by Stefan.

[1], 6cd18e711dd8075 (block: destroy bdi before blockdev is
unregistered)

Reported-by: Stefan Seyfried <stefan.seyfried@googlemail.com>
Cc: NeilBrown <neilb@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org (v4.0)
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>