Re: [PATCHv4 4/8] khugepaged: Drain LRU add pagevec after swapin

[Andrew Morton]

On Thu, 16 Apr 2020 19:00:22 +0300 "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> wrote:

> __collapse_huge_page_isolate() may fail due to extra pin in the LRU add
> pagevec. It's pretty common for swapin case: we swap in pages just to
> fail due to the extra pin.
> 
> Drain LRU add pagevec on successful swapin.

I don't see how this patch can do anything to prevent
__collapse_huge_page_isolate() from failing, which is what the
changelog implies.

Can we have a more detailed changelog, please?