Re: [RFC PATCH 2/2] selftests/mm: Test per-open gup_test pin ownership

["David Hildenbrand (Arm)" <david@kernel.org>]

On 9/21/26 11:42, Richard Cheng wrote:
> Long-term pin state should be isolated between independently opened
> gup_test file descriptions, while descriptors created with dup() should
> continue to share the state associated with their struct file.
> 
> Add tests using 2 independently opened gup_test descriptors. Verify that
> stopping or closing the second descriptor doesn't disturb the first
> descriptor's pin, that another START on the same descriptor fails with
> EINVAL, and that READ fails with EINVAL after STOP.
> 
> Close the descriptor used by the existing test matrix before running the
> ownership tests. Record whether gup_test was initially available so that
> a later open failure is reported as a failure instead of being hidden as
> a skip.
> 
> Also exercise the shared-file-description case: start a pin through the
> original descriptor, verify that START through a duplicate fails with
> EINVAL, close the original descriptor, and use the duplicate to READ and
> STOP the pin
> 
> Reviewed-by: Koba Ko <kobak@nvidia.com>
> Signed-off-by: Richard Cheng <icheng@nvidia.com>
> ---
>  tools/testing/selftests/mm/gup_longterm.c | 258 +++++++++++++++++++++-
>  1 file changed, 256 insertions(+), 2 deletions(-)

Sorry, we won't be adding tests for gup_test interface functionality. This is a
testing interface.

(I'd be quite surprised if no LLM was inovolved in writing this patch :) )

-- 
Cheers,

David