Re: Error in generic/397 test script?

[Eric Biggers <ebiggers@kernel.org>]

On Mon, Jan 20, 2025 at 03:43:46PM +0000, David Howells wrote:
> David Howells <dhowells@redhat.com> wrote:
> 
> > However, in this case (in which I'm running these against ceph), I don't think
> > that the find should return nothing, so it's not a bug in the test script per
> > se.
> 
> Turned out that I hadn't enabled XTS and so the tests for xts(aes) failed and
> produced no files.
> 
> David

AES-XTS support is mandatory for fscrypt, as is documented in fscrypt.rst.  The
filesystems that support fscrypt select FS_ENCRYPTION_ALGS, which has "imply
CRYPTO_XTS" and "imply CRYPTO_AES".  As explained in the comment just above it,
the reason that it's "imply" rather than "select" is so people can disable the
generic implementations of these algorithms if they know that an optimized
implementation will always be available.

It would be enlightening to understand what the issue was here.  Did you
explicitly disable these options, overriding the imply, without providing a
replacement?  Or was this another issue specific to unmerged kernel patches?

- Eric