Re: [PATCH v2 2/7] mm/selftests: add max_vma_count tests

[David Hildenbrand]

> + * test_suite_setup - Set up the VMA layout for VMA count testing.
> + *
> + * Sets up the following VMA layout:
> + *
> + * +----- base_addr
> + * |
> + * V
> + * +--------------+----------------------+--------------+----------------+--------------+----------------+--------------+-----+----------------+--------------+
> + * |  Guard Page  |                      |  Guard Page  |  Extra Map 1   | Unmapped Gap |  Extra Map 2   | Unmapped Gap | ... |  Extra Map N   | Unmapped Gap |
> + * |  (unmapped)  |      TEST_AREA       |  (unmapped)  | (mapped page)  |  (1 page)    | (mapped page)  |  (1 page)    | ... | (mapped page)  |  (1 page)    |
> + * |   (1 page)   | (unmapped, 3 pages)  |   (1 page)   |    (1 page)    |              |    (1 page)    |              |     |    (1 page)    |              |
> + * +--------------+----------------------+--------------+----------------+--------------+----------------+--------------+-----+----------------+--------------+
> + * ^              ^                      ^              ^                                                                  ^
> + * |              |                      |              |                                                                  |
> + * +--GUARD_SIZE--+                      |              +-- EXTRA_MAPS points here             Sufficient EXTRA_MAPS to ---+
> + *    (PAGE_SIZE) |                      |                                                         reach MAX_VMA_COUNT
> + *                |                      |
> + *                +--- TEST_AREA_SIZE ---+
> + *                |   (3 * PAGE_SIZE)    |
> + *                ^
> + *                |
> + *                +-- TEST_AREA starts here
> + *

Just wondering if we could find a different name than "guard page" here, 
to not confuse stuff with guard ptes

Will the current "guard page" we a valid vma or just a hole?

--
Cheers

David / dhildenb