[LU-13895] Prevent discovery on peer that is being deleted

• Type: Bug
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.15.0
• Severity: 3
• Assignee: Chris Horn
• Reporter: Chris Horn

Description

In lnet_peer_add_nid(), we may delete a peer associated with the NID we're attempting to add. If so, we should avoid any further discovery actions on that peer, and ensure any waiters on the peer are woken so they can release their references and allow the peer to be deleted.