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Date:   Thu, 4 Nov 2021 15:00:36 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     Linus Torvalds <torvalds@linux-foundation.org>,
        Christoph Hellwig <hch@lst.de>
Cc:     linux-arch@vger.kernel.org, Ira Weiny <ira.weiny@intel.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>
Subject: flush_dcache_page vs kunmap_local
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In https://lore.kernel.org/lkml/CAHk-=wijdojzo56FzYqE5TOYw2Vws7ik3LEMGj9SPQaJJ+Z73Q@mail.gmail.com/
Linus offers the opinion that kunmap calls should imply a
flush_dcache_page().  Christoph added calls to flush_dcache_page()
in commit 8dad53a11f8d.  Was this "voodoo programming", or was there
a real problem being addressed?