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From: Martin Wege <martin.l.wege@gmail.com>
Date: Mon, 18 Dec 2023 09:37:06 +0100
Message-ID: <CANH4o6NcrFz6EKDcfq1daaSpmOuCebYA-A3u3Bk_+kPtJWBLYA@mail.gmail.com>
Subject: Re: umount.nfs: /mnt: block devices not permitted on fs
To: Linux NFS Mailing List <linux-nfs@vger.kernel.org>
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On Thu, Nov 30, 2023 at 1:26=E2=80=AFPM Benjamin Coddington <bcodding@redha=
t.com> wrote:
>
> On 29 Nov 2023, at 22:45, Martin Wege wrote:
>
> > ?
> >
> > On Fri, Nov 24, 2023 at 9:57=E2=80=AFAM Martin Wege <martin.l.wege@gmai=
l.com> wrote:
> >>
> >> Hello,
> >>
> >> We get a umount.nfs: /mnt: block devices not permitted on fs in a snap
> >> container on Ubuntu.
> >>
> >> Can anyone explain what is going wrong?
>
> Something in umount is calling umount_error() with -EACCES.  I admit that
> error message makes no sense, it seems to be cruft.

Can this be fixed, please?

>
> Maybe you can run the umount in gdb with a breakpoint on umount_error() a=
nd
> send along the stack.

This is much more difficult than I expected - the target system is a
Ubuntu Core system, which uses SNAPs, and debugging there is a
disaster.

Does umount have an extended debug output?

Thanks,
Martin