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crypto: hisilicon/qm - fix deadlock for remove driver
When remove the driver and executing the task occur at the same time,
the following deadlock will be triggered:
Chain exists of:
sva_lock --> uacce_mutex --> &qm->qps_lock
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&qm->qps_lock);
lock(uacce_mutex);
lock(&qm->qps_lock);
lock(sva_lock);
And the lock 'qps_lock' is used to protect qp. Therefore, it's reasonable
cycle is to continue until the qp memory is released. So move the release
lock infront of 'uacce_remove'.
Signed-off-by: Yang Shen <shenyang39@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>