Hi Maik,
Sorry for the late reply.
On Wed, Feb 25, 2026 at 11:02:05AM +0100, Maik Nergert wrote:
> Hi,
>
> > if you rollback to the old kernel, with the mount options as when you
> > are able to trigger the problem, what will mount show for the
> > negotiated wsize and rsize?
>
> > So I suspect the negotiated rsize and wsize is then not 1M, correct,
> > I.e what are the negotiated sizes?
>
>
> Mounting without specific rsize/wsize:
>
> Kernel 6.1.158 negotiated (from Dell Powerscale OneFS aka Isilon)
> rsize=1047672,wsize=1047532 and no errors
>
> Kernel 6.1.162 negotiated
> rsize=1048576,wsize=1048576 and Input/output error
>
>
> Kernel 6.1.158 negotiated (from Debian Bookworm NFS)
> rsize=1048576,wsize=1048576 and no errors
>
>
>
> > One additional question: Do you have a test system exposing the
> > problem where you can try as well the kernel from trixie, unstable or
> > experimental to gather an idea if it affects still upper kernels? I'm
> > asking because 2b092175f5e3 ("NFS: Fix inheritance of the block sizes
> > when automounting") is in v6.19-rc1 and got backported to v6.18.2,
> > v6.17.13, v6.12.63, v6.6.120 and v6.1.160.
>
> Linux trixie-test 6.12.73+deb13-amd64
>
> mount -t nfs -o vers=4.2
> Results in "rsize=1048576,wsize=1048576" and Input/output error
>
> mount -t nfs -o vers=4.2,rsize=1048576,wsize=1048576
> Results in "rsize=1047672,wsize=1047532" and no errors
>
>
> I would say that the commit corrected the wrong values (<1M to the correct
> 1M) and that in this case there is no problem with the kernel.
> It now looks much more like the "Powerscale OneFS" NFS server is somehow
> incorrect.
>
> <1M works for us, so I think we should just specify a value for automount
> and live with it and create a Dell support ticket.
Then yes, indeed it looks lie an issue on the Oowerscale OneFS NFS
server. I'm keeping this bug a bit open still, as I plan to ask the
NFS upstream developer if they can have a look and post as a question
if this might be worth beeing detected and mitigated on the kernel
side (or ignored and defer to Dell).
I will update this bug later (and maybe close it then).
Have you heard something back from Dell yet?
Regards,
Salvatore
