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Date:   Sat, 26 Dec 2020 21:41:06 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     "Kirill A. Shutemov" <kirill@shutemov.name>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        Hugh Dickins <hughd@google.com>,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Will Deacon <will@kernel.org>,
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        Linux-MM <linux-mm@kvack.org>,
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        Andrew Morton <akpm@linux-foundation.org>,
        Vinayak Menon <vinmenon@codeaurora.org>,
        Android Kernel Team <kernel-team@android.com>
Subject: Re: [PATCH 1/2] mm: Allow architectures to request 'old' entries
 when prefaulting
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On Sat, Dec 26, 2020 at 11:43:35PM +0300, Kirill A. Shutemov wrote:
> +static struct page *next_stable_page(struct page *page, struct vm_fault *vmf,
> +				     struct xa_state *xas, pgoff_t end_pgoff)

A "stable page" means one that doesn't currently have an outstanding
write (see wait_for_stable_page()).  It's really "Next trivially
insertable page".  I might call it "next_uptodate_page()" and gloss
over the other reasons this might fail to return a page.