[LU-7875] Suspect locking cleanup in mdt_reint_unlink()

• Type: Bug
• Resolution: Not a Bug
• Priority: Minor
• Fix Version/s: Lustre 2.11.0
• Severity: 3
• Assignee: Lai Siyao
• Reporter: Oleg Drokin

Description

In mdt_reint_unlink we have suspect locking cleanup on error:

        rc = mdt_reint_object_lock(info, mc, child_lh, lock_ibits,
                                   cos_incompat);
        if (rc != 0)
                GOTO(unlock_child, rc);
...
unlock_child:
        mdt_unlock_slaves(info, mc, MDS_INODELOCK_UPDATE, s0_lh, s0_obj, einfo,
                          rc);
        mdt_object_unlock(info, mc, child_lh, rc);
unlock_parent:
        mdt_object_unlock(info, mp, parent_lh, rc);
put_child:
        mdt_object_put(info->mti_env, mc);
put_parent:
        mdt_object_put(info->mti_env, mp);

So it looks like we failed a child lock and then jus jump to unlock it anyway?
need to make that goto to unlock_parent?
Also need to check if the below lock_slaves call to unlock slaves would be fine too. Not even sure why the unlock order is reversed.