(follow-up) "Stale NFS file handle" for NFS exported UFS from r252435

On 07/10/2013 14:32, Claude Buisson wrote:
> Hi,
>
> Upgrading a CURRENT amd64 pure UFS system (watson) from r249744 to r253007, I
> have hit the following:
>
> claude_at_zorglub$ mount_nfs watson:/home /mnt
> claude_at_zorglub$ /bin/ls /mnt/
> claude          doc.old         ports.old       sysref
> distfiles       obj             portsperso      xorg-dev
> doc             ports           src             xtrafiles
> claude_at_zorglub$ /bin/ls /mnt/claude
> ls: /mnt/claude: Stale NFS file handle
> claude_at_zorglub$ /bin/ls /mnt/ports.old
> CHANGES         UPDATING        dns             multimedia      textproc
> COPYRIGHT       accessibility   editors         net             www
> ...
>
> some directories may be listed, for the others the result is "Stale NFS file handle"
>
> This exists for a 8.4-STABLE client system, for a 9.1-STABLE client system, and
> also with a local mount (localhost) on the server system itself.
>
> I checked with memsticks of official snapshots (to eliminate the influence of
> local patches and customized kernels), with the result:
>
> FreeBSD-10.0-CURRENT-amd64-20130630-r252387-memstick is not affected
>
> FreeBSD-10.0-CURRENT-amd64-20130707-r252887-memstick is affected
>
> Doing a binary search on the kernel source (without any patch) lead to the
> "culprit":
>
> ----------------------------------------------------------------------
> Author: pfg
> Date: Mon Jul  1 03:00:15 2013
> New Revision: 252435
> URL: http://svnweb.freebsd.org/changeset/base/252435
>
> Log:
>     Change i_gen in UFS to an unsigned type.
>
>     In UFS, i_gen is a random generated value and there is not way for
>     it to be negative. Actually, the value of i_gen is just used to
>     match bit patterns and it is of not consequence if the values are
>     signed or not.
>
>     Following other filesystems, set it to unsigned and use it as such,
>
>     Discussed by:	mckusick
>     Reviewed by:	mckusick (previous version)
>     MFC after:	4 weeks
>
> Modified:
>     head/sys/ufs/ffs/ffs_vfsops.c
>     head/sys/ufs/ufs/dinode.h
>     head/sys/ufs/ufs/inode.h
>     head/sys/ufs/ufs/ufs_extattr.c
> ----------------------------------------------------------------------
>
> which is entirely UFS (not NFS) related.
>

Reverting 252435 + 252437 and rebuilding the kernel seems to give back a working
system.

Claude Buisson