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Date:   Thu, 21 Apr 2022 20:28:32 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Nico Pache <npache@redhat.com>
Cc:     linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        Michael Ellerman <mpe@ellerman.id.au>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Paul Mackerras <paulus@samba.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Andrew Morton <akpm@linux-foundation.org>,
        Nicholas Piggin <npiggin@gmail.com>,
        Logan Gunthorpe <logang@deltatee.com>,
        Hari Bathini <hbathini@linux.ibm.com>,
        "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>,
        Yang Shi <shy828301@gmail.com>,
        Miaohe Lin <linmiaohe@huawei.com>,
        William Kucharski <william.kucharski@oracle.com>,
        Hugh Dickins <hughd@google.com>
Subject: Re: [RFC 1/3] mm: change vma_is_anonymous to vma_is_private_anon
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References: <20220421190533.1601879-1-npache@redhat.com>
 <20220421190533.1601879-2-npache@redhat.com>
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On Thu, Apr 21, 2022 at 03:05:31PM -0400, Nico Pache wrote:
> The vma_is_anonymous function isn't fully indicative of what it checks.
> 
> Without having full knowledge of the mmap process, one may incorrectly
> assume this covers all types of anonymous memory; which is not the case.

Is your complaint that anonymous memory can also be found in file VMAs
that were mapped with MAP_PRIVATE?  ie COWed pages?

I don't think renaming this function is appropriate.  It's whether
the VMA is anonymous, not whether the VMA can contain anonymous
pages.