Re: Question on nfs40_discover_server_trunking.

[Ben Greear <greearb@candelatech.com>]

On 01/18/2013 01:33 PM, Chuck Lever wrote:
>
> On Jan 18, 2013, at 4:28 PM, Ben Greear <greearb@candelatech.com> wrote:
>
>> Any chance the STALE_CLIENTID case needs a 'break'?
>
> I don't think so.  LEASE_CONFIRM is set, and we want to wake the state renewal thread.
>
>>
>> Twice I've seen kernel crashes after the nfs40_walk_client_list
>> failed (though code comments say it should never fail).
>
> nfs40_walk_client_list() is looking for an nfs_client that is supposed to already be in the nfs_client list.  If the search fails, that's a bug.
>
> Eyeball the contents of your nfs_client list.  You should find an appropriate nfs_client in there, and then figure out why the search doesn't find it.

Ok, I think I found another issue.

nfs4_client_init does not initialize 'old', but passes it to nfs4_discover_server_trunking.

That gets passed to the detect_trunking operation, which is nfs40_discover_server_trunking
or nfs41_discover_server_trunking.

This will call walk_client_list, which also may not ever assign a value to
'result'.

The code in walk_client_list always dereferences result, however.

So, that is probably why my system blows up shortly after the 'impossible'
error message...

Maybe initialize result to NULL in nfs4[10]_walk_client_list and properly check
for null result in calling code?

Thanks,
Ben


-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com