Re: [PATCH v2 0/2] nfsd: fix unhashing races in nfsv4 stateid handling

[Anna Schumaker <Anna.Schumaker@netapp.com>]

Hi Jeff,

On 08/24/2015 12:41 PM, Jeff Layton wrote:
> v2:
> - fix the fault injection code to handle the prototype change to
>   unhash_lock_stateid
> 
> Slightly updated set, to fix a problem that Wu found when enabling the
> nfsd fault injection code. Original cover-letter follows:
> 
> -------------------------[snip]-------------------
> 
> I hadn't heard from Andrew in a while so I'm not 100% clear on whether
> his patches had fixed the race that he had spotted in the NFSv4
> unhashing code.
> 
> Still, once he had done the analysis, the problem was clear. I think
> this patchset should fix the problem in a relatively clean way. I've
> run some tests against this and it seems to not have broken anything,
> but I haven't been able to reproduce the actual race so I can't
> verify that this fixes it.
> 
> Andrew, Anna, if you are able to do so could you test these patches
> and let us know whether this fixes those races?

I just did a quick test, and it looks like my problem has been fixed.  I'll do more in-depth testing tomorrow, just to make sure.

Thanks for working on this!

Anna
> 
> Jeff Layton (2):
>   nfsd: ensure that the ol stateid hash reference is only put once
>   nfsd: ensure that delegation stateid hash references are only put once
> 
>  fs/nfsd/nfs4state.c | 84 +++++++++++++++++++++++++++++++++--------------------
>  1 file changed, 53 insertions(+), 31 deletions(-)
>