Re: [PATCH v3] mm/page_isolation: guard against possible putback unisolated page

From: Andrew Morton
Date: Tue Sep 14 2021 - 22:09:54 EST


On Tue, 14 Sep 2021 19:45:08 +0800 Miaohe Lin <linmiaohe@xxxxxxxxxx> wrote:

> Isolating a free page in an isolated pageblock is expected to always work
> as watermarks don't apply here. But if __isolate_free_page() failed, due
> to condition changes, the page will be left on the free list. And the page
> will be put back to free list again via __putback_isolated_page(). This may
> trigger VM_BUG_ON_PAGE() on page->flags checking in __free_one_page() if
> PageReported is set. Or we will corrupt the free list because list_add()
> will be called for pages already on another list. Add a VM_WARN_ON() to
> complain about this change.

Are you able to identify a Fixes: here?

Is a cc:stable justified?