Re: unmount(2) returning EROFS

[Martin Husemann <martin%duskware.de@localhost>]

On Wed, Nov 06, 2024 at 02:47:01PM +0100, Edgar Fuß wrote:
> If I mount the snapshot read-only (-r), the problem disappears.
> 
> Apart from unmount(2) not documenting EROFS, why the hell can unmounting 
> fail with that error and why only if the fs is NOT mounted r/o?

A read-only mount can not have any pending buffers to write before unmounting.
Now apparently either there are bogus buffers pending to flush for your unmount
(which we should examing closer), or the error is generated despite no such
buffers existing (which would mean the failure could be ignored).

I think this has been seriously reworked in newer versions.

Martin