RDMA/erdma: Hold QP references for AE and CM processing

AE QP fatal events and iWARP CM paths load QPs from dev->qp_xa
and then use or reference them outside the xarray lock.
erdma_destroy_qp() can drop the destroy-path reference and free QP
resources while such a lookup is in flight.

Add erdma_qp_get_by_qpn() to acquire a kref under the xarray
lock with kref_get_unless_zero(). Remove the QP from the xarray
before dropping the destroy-path reference so no new lookup can acquire
it while destruction waits for existing users.

Fixes: 155055771704 ("RDMA/erdma: Add verbs implementation")
Signed-off-by: Cheng Xu <chengyou@linux.alibaba.com>
Link: https://patch.msgid.link/20260730124357.12976-2-chengyou@linux.alibaba.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>

0 files changed, 0 insertions, 0 deletions