Re: [PATCH 1/2] mm: Remove redundant test from find_get_pages_contig

[Kirill A. Shutemov]

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