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Date:   Thu, 4 Nov 2021 18:38:56 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Christoph Hellwig <hch@lst.de>,
        linux-arch <linux-arch@vger.kernel.org>,
        Ira Weiny <ira.weiny@intel.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: flush_dcache_page vs kunmap_local
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On Thu, Nov 04, 2021 at 08:30:55AM -0700, Linus Torvalds wrote:
> Why did this come up? Do you actually have some hardware or situation
> that cares?

Oh, we're doing review of the XFS/iomap folio patches, which led to
looking at zero_user_segments(), and I realised that memzero_page()
was now functionally identical to zero_user().  And you'd been quite
specific about not having flush_dcache_page() in there, so ... I wondered
if you'd had a change of mind.