Re: [PATCH RFC v3] mm: Proper document tail pages fields for folio

[Matthew Wilcox]

On Wed, Aug 16, 2023 at 03:33:30PM +0200, David Hildenbrand wrote:
> My simple tests passed so far. If there isn't something obvious missing,
> I can do more testing and send this as an official patch.

I think you missed one:

+++ b/mm/swapfile.c
@@ -1490,7 +1490,7 @@ int swp_swapcount(swp_entry_t entry)

        page = vmalloc_to_page(p->swap_map + offset);
        offset &= ~PAGE_MASK;
-       VM_BUG_ON(page_private(page) != SWP_CONTINUED);
+       VM_BUG_ON(page_swap_entry(page).val != SWP_CONTINUED);

        do {
                page = list_next_entry(page, lru);

I'm not smart enough to understand the use of the one in
add_swap_count_continuation().  Maybe that also needs to be fixed?
Maybe it should be fixed for consistency anyway.