Re: [PATCH v2 0/1] NFSv4.2: Fix NFS4ERR_STALE with inter server copy

["J. Bruce Fields" <bfields@fieldses.org>]

On Wed, Oct 07, 2020 at 09:25:12PM -0400, Dai Ngo wrote:
> This cover email is intended for including my test results.
> 
> This patch adds the ops table in nfs_common for knfsd to access
> NFS client modules without calling these functions directly.
> 
> The client module registers their functions and deregisters them
> when the module is loaded and unloaded respectively.
> 
>  fs/nfs/nfs4file.c       |  44 ++++++++++++--
>  fs/nfs/nfs4super.c      |   6 ++
>  fs/nfs/super.c          |  20 +++++++
>  fs/nfs_common/Makefile  |   1 +
>  fs/nfs_common/nfs_ssc.c | 136 +++++++++++++++++++++++++++++++++++++++++++
>  fs/nfsd/Kconfig         |   2 +-
>  fs/nfsd/nfs4proc.c      |   3 +-
>  include/linux/nfs_ssc.h |  77 ++++++++++++++++++++++++
>  8 files changed, 281 insertions(+), 8 deletions(-)
> 
> Test Results:
> 
> Upstream version used for testing:  5.9-rc5
> 
> |----------------------------------------------------------|
> |  NFSD  |  NFS_FS  |  NFS_V4  |       RESULTS             |
> |----------------------------------------------------------|
> |   m    |    y     |    m     | inter server copy OK      |
> |----------------------------------------------------------|
> |   m    |    m     |    m     | inter server copy OK      |
> |----------------------------------------------------------|
> |   m    |    m     |   y (m)  | inter server copy OK      |
> |----------------------------------------------------------|
> |   m    |    y     |    y     | inter server copy OK      |
> |----------------------------------------------------------|
> |   m    |    n     |    n     | NFS4ERR_STALE error       |
> |----------------------------------------------------------|

Why are there two?  And how are you getting that NFS4ERR_STALE case?
NFSD_V4_2_INTER_SSC depends on NFS_FS, so it shouldn't be possible to
build server-to-server-copy support without building the client.  And if
you don't build NFSD_V4_2_INTER_SSC at all, then I think it should be
returning NOTSUPP instead of STALE.

--b.

> |----------------------------------------------------------|
> |  NFSD  |  NFS_FS  |  NFS_V4  |        RESULTS            |
> |----------------------------------------------------------|
> |   y    |    y     |    m     | inter server copy OK      |
> |----------------------------------------------------------|
> |   y    |    m     |    m     | inter server copy OK      |
> |----------------------------------------------------------|
> |   y    |    m     |   y (m)  | inter server copy OK      |
> |----------------------------------------------------------|
> |   y    |    y     |    y     | inter server copy OK      |
> |----------------------------------------------------------|
> |   y    |    n     |    n     | NFS4ERR_STALE error       |
> |----------------------------------------------------------|
> 
> NOTE:
> When NFS_V4=y and NFS_FS=m, the build process automatically builds
> with NFS_V4=m and ignores the setting NFS_V4=y in the config file. 
> 
> This probably due to NFS_V4 in fs/nfs/Kconfig is configured to
> depend on NFS_FS.