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Date:   Fri, 10 Nov 2023 18:15:34 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     Kefeng Wang <wangkefeng.wang@huawei.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        David Hildenbrand <david@redhat.com>,
        Gregory Price <gregory.price@memverge.com>
Subject: Re: [PATCH v2 2/7] fs/proc/page: use a folio in stable_page_flags()
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References: <20231110033324.2455523-1-wangkefeng.wang@huawei.com>
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On Fri, Nov 10, 2023 at 11:33:19AM +0800, Kefeng Wang wrote:
> Replace nine compound_head() calls with one page_folio().

But that's not all it does.  Honestly, when you write these kind of
things, I wonder if you understand what you're doing.

After this patch, if we report on a tail page, we set (some of) the
flags according to how its head page is set.  Before, we would have not
reported on it at all.

This was THE ENTIRE POINT of Greg's patch.  And why his patch made sense
and yours is nonsense.  Andrew, please drop this patch series.