> On Mar 23, 2019, at 9:04 PM, Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote:
>
>
> static inline struct page *find_subpage(struct page *page, pgoff_t offset)
> {
> + unsigned long index = page_index(page);
> +
> VM_BUG_ON_PAGE(PageTail(page), page);
> - VM_BUG_ON_PAGE(page->index > offset, page);
> - VM_BUG_ON_PAGE(page->index + (1 << compound_order(page)) <= offset,
> - page);
> - return page - page->index + offset;
> + VM_BUG_ON_PAGE(index > offset, page);
> + VM_BUG_ON_PAGE(index + (1 << compound_order(page)) <= offset, page);
> + return page - index + offset;
> }
>
>
>> [ 56.915812] page dumped because: VM_BUG_ON_PAGE(index + compound_order(page)
>> <= offset)
>
> Yeah, you were missing the '1 <<' part.
>
Is a V5 patch coming incorporating these?
