Re: [PATCH -RFC] ext4: add feature file to advertise that ext4 supports idmapped mounts

Christoph Hellwig
2021-04-15T05:54:13Z

On Wed, Apr 14, 2021 at 04:47:10PM -0400, Theodore Ts'o wrote:
> On Mon, Apr 12, 2021 at 06:41:20PM -0400, Theodore Ts'o wrote:
> > In the ideal world, if the kernel wasn't compiled with the necessary
> > CONFIG options enabled, it's desirable of the test can detect that
> > fact and skip running the test instead failing and forcing the person
> > running the test to try to figure out whether this is a legitmate file
> > system bug or a just a test setup bug.
>
> So it would make it easier for me to manage running xfstests on ext4
> if I had added something like this to ext4 and sent it to Linus before
> v5.12 is released. What do folks think?

Completely stupid. This is a VFS-level feature and we need to have
proper VFS-level testing (which we have through creating a mount
with the option), not fs-specific band aids.