On Thu, Nov 22, 2018 at 01:32:23PM -0800, Matthew Wilcox wrote: > After we establish a reference on the page, we check the pointer continues > to be in the correct position in i_pages. There's no need to check the > page->mapping or page->index afterwards; if those can change after we've > got the reference, they can change after we return the page to the caller. Hm. IIRC, page->mapping can be set to NULL due truncation, but what about index? When it can be changed? Truncation doesn't touch it. -- Kirill A. Shutemov