Re: PROBLEM: NFS client IO fails with ERESTARTSYS when another mount point with the same export is unmounted with force [NFS] [SUNRPC]

From: Trond Myklebust
Date: Wed Feb 21 2024 - 08:48:45 EST


On Wed, 2024-02-21 at 16:20 +0800, Zhitao Li wrote:
> [You don't often get email from zhitao.li@xxxxxxxxxx. Learn why this
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>
> Hi, everyone,
>
> - Facts:
> I have a remote NFS export and I mount the same export on two
> different directories in my OS with the same options. There is an
> inflight IO under one mounted directory. And then I unmount another
> mounted directory with force. The inflight IO ends up with "Unknown
> error 512", which is ERESTARTSYS.
>

All of the above is well known. That's because forced umount affects
the entire filesystem. Why are you using it here in the first place? It
is not intended for casual use.

--
Trond Myklebust
Linux NFS client maintainer, Hammerspace
trond.myklebust@xxxxxxxxxxxxxxx