Re: [PATCH 2/2] We should clear NFS_DELEGATED_STATE after return delegation

[Bian Naimeng <biannm@cn.fujitsu.com>]

>>>> I still don't see why this should be necessary. In the case of a server
>>>> reboot or network partition, the state recovery thread ought to be
>>>> taking care of this for us.
>>>>
>>>    A open state can be found at nfsi->open_states and owner->so_states always, but
>>>   it not be found at nfsi->open_files until we call nfs4_intent_set_file.
>>>
>>>    At _nfs4_do_open, we will invoke nfs4_return_incompatible_delegation to return a 
>>>   delegation,  a open stateid which set NFS_DELEGATED_STATE bit may not be found at
>>>   nfsi->open_files, but it still at nfsi->open_states, so we do not clear 
>>>   NFS_DELEGATED_STATE bit for it.
>>>
>>>    Then _nfs4_do_open will find it by nfs4_get_open_state, and we still use it
>>>   as a delegation, some error will occur.
>>>
>> OK. I see agree that is a race, but AFAICS, your fix means that we end
>> up with an nfs_state structure that has cleared NFS_DELEGATED_STATE, but
>> that did not recover its open stateid.
>>
> 
>   Hi trond, i am not sure my opinion is right.
> 
>   If the state not at nfsi->open_states, i think maybe that means it's not a open stateid,
>   it just a old state we want reuse it. After we update it, it become a open stateid.
> 

Hi trond, have you got a idea to solve this race?

-- 
Regards
Bian Naimeng