[LU-14957] mdd_migrate() sends RPC with a local transaction running

• Type: Bug
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.15.0
• Affects Version/s: Upstream
• Severity: 3
• Assignee: Lai Siyao
• Reporter: Alex Zhuravlev

Description

if a remote host is down for a while, then local MDS may get stuck as well

Call Trace:
 dump_stack+0x85/0xc0
 ptlrpc_queue_wait+0x27e/0x290 [ptlrpc]
 osp_remote_sync+0x122/0x1a0 [osp]
 osp_md_xattr_list+0x4d4/0x7f0 [osp]
 mdd_iterate_xattrs+0xac/0xa30 [mdd]
 ? mdo_declare_xattr_set+0x330/0x330 [mdd]
 ? down_write_nested+0x73/0xb0
 mdd_migrate_object+0x18c1/0x2b80 [mdd]
 mdd_migrate+0x385/0x1740 [mdd]
 ? mdt_object_lock_internal+0x1d3/0x3f0 [mdt]
 mdt_reint_migrate+0x1bf6/0x3260 [mdt]
 ? lustre_msg_add_version+0x1c/0x90 [ptlrpc]
 mdt_reint_rec+0x117/0x240 [mdt]
 mdt_reint_internal+0x9e1/0xbd0 [mdt]
 mdt_reint+0x57/0x100 [mdt]
 tgt_request_handle+0xbe0/0x1970 [ptlrpc]