Bug#659111: [2.6.31 -> 2.6.32 regression] Files on NFS4 become unwritable,, but OK after explicit stat

[Jonathan Nieder <jrnieder@gmail.com>]

Rik Theys wrote:

> Can this commit be backported to the 3.2 kernel in sid?
> It applies and I have tested it in the past against the 3.2.4 kernel.

Just for the record: we are talking about

 v3.3-rc1~116^2~1 "NFSv4: Save the owner/group name string when doing
                  open", 2012-01-07

It looks safe to me, too.  It is too large to follow the rules of
Greg's 3.2.y-stable kernel to the letter, but I think we should apply
it.

For 2.6.32.y-longterm, I would be happier with a more minimal patch.
Where can one find more information about the rpciod hang described
in the commit message to 80e52aced138b ("NFSv4: Don't do idmapper
upcalls for asynchronous RPC calls", 2009-08-09)?  Maybe there is
some alternative fix to that.

I would also be very much interested to hear how well the following
series against 2.6.32.y does:

 v2.6.33-rc1~54^2~7 "rpc: add a new priority in RPC task", 2009-12-14
 v2.6.33-rc1~54^2~5 "nfs: make recovery state manager operations
                    privileged", 2009-12-14
 v3.3-rc1~116^2~1 "NFSv4: Save the owner/group name string when doing
                  open", 2012-01-07

Backported patches are at <http://bugs.debian.org/659111#50>.