Re: [PATCH v7 08/14] mm,hwpoison: rework soft offline for free pages

[HORIGUCHI NAOYA(堀口 直也)]

On Tue, Sep 22, 2020 at 03:56:44PM +0200, Oscar Salvador wrote:
> When trying to soft-offline a free page, we need to first take it off the
> buddy allocator.
> Once we know is out of reach, we can safely flag it as poisoned.
> 
> take_page_off_buddy will be used to take a page meant to be poisoned off
> the buddy allocator. take_page_off_buddy calls break_down_buddy_pages,
> which splits a higher-order page in case our page belongs to one.
> 
> Once the page is under our control, we call page_handle_poison to set it
> as poisoned and grab a refcount on it.
> 
> Signed-off-by: Oscar Salvador <osalvador@xxxxxxx>

Acked-by: Naoya Horiguchi <naoya.horiguchi@xxxxxxx>