[LU-5266] LBUG on Failover -ldlm_process_extent_lock()) ASSERTION( lock->l_granted_mode != lock->l_req_mode )

• Type: Bug
• Resolution: Fixed
• Priority: Blocker
• Fix Version/s: Lustre 2.6.0, Lustre 2.5.4
• Affects Version/s: Lustre 2.6.0
• Labels: HB
• Environment: Hyperion - 2.5.60 build 2538
• Severity: 3
• Assignee: Hongchao Zhang
• Reporter: Cliff White (Inactive)

Description

After hard failover of devices to server iws19, server wedged, then hit LBUG.
Services never complete recovery, and appear to either restart the timer or something:

Jun 27 10:08:53 iws19 kernel: Lustre: lustre-OST000c: Will be in recovery for at least 2:30, or until 316 clients reconnect
Jun 27 10:11:53 iws19 kernel: Lustre: lustre-OST000c: recovery is timed out, evict stale exports
Jun 27 10:18:30 iws19 kernel: Lustre: lustre-OST000c: Client c52d4856-d1df-b87b-911c-f1bfbc23a24d (at 192.168.124.182@o2ib) reconnecting, waiting for 316 clients in recovery for 2:27

The server reports being cpu-bound prior to the failure
Console log attached - unfortunately the dump after the LBUG failed.

Issue Links

• is related to: LU-5496 fix for LU-5266
• is related to: LU-2827 mdt_intent_fixup_resent() cannot find the proper lock in hash