Re: [xfstests PATCH] ext4/053: fix the rejected mount option testing

[Lukas Czerner <lczerner@redhat.com>]

On Mon, May 09, 2022 at 04:42:03PM -0700, Eric Biggers wrote:
> On Sat, Apr 30, 2022 at 12:21:30PM -0700, Eric Biggers wrote:
> > From: Eric Biggers <ebiggers@google.com>
> > 
> > 'not_mnt OPTIONS' seems to have been intended to test that the
> > filesystem cannot be mounted at all with the given OPTIONS, meaning that
> > the mount fails as opposed to the options being ignored.  However, this
> > doesn't actually work, as shown by the fact that the test case 'not_mnt
> > test_dummy_encryption=v3' is passing in the !CONFIG_FS_ENCRYPTION case.
> > Actually ext4 ignores this mount option when !CONFIG_FS_ENCRYPTION.
> > (The ext4 behavior might be changed, but that is besides the point.)
> > 
> > The problem is that the do_mnt() helper function is being misused in a
> > context where a mount failure is expected, and it does some additional
> > remount tests that don't make sense in that context.  So if the mount
> > unexpectedly succeeds, then one of these later tests can still "fail",
> > causing the unexpected success to be shadowed by a later failure, which
> > causes the overall test case to pass since it expects a failure.
> > 
> > Fix this by reworking not_mnt() and not_remount_noumount() to use
> > simple_mount() in cases where they are expecting a failure.  Also fix
> > up some of the naming and calling conventions to be less confusing.
> > Finally, make sure to test that remounting fails too, not just mounting.
> > 
> > Signed-off-by: Eric Biggers <ebiggers@google.com>
> > ---
> >  tests/ext4/053 | 148 ++++++++++++++++++++++++++-----------------------
> >  1 file changed, 78 insertions(+), 70 deletions(-)
> 
> Lukas, any thoughts on this patch?  You're the author of this test.
> 
> - Eric

Haven't tested it myself but the change looks fine, thanks.

You can add
Reviewed-by: Lukas Czerner <lczerner@redhat.com>