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Date:   Sun, 26 Apr 2020 23:25:00 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Ira Weiny <ira.weiny@intel.com>
Cc:     Christoph Hellwig <hch@infradead.org>,
        linux-kernel@vger.kernel.org,
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        Helge Deller <deller@gmx.de>,
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Subject: Re: [PATCH 4/5] arch/kmap_atomic: Consolidate duplicate code
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On Sun, Apr 26, 2020 at 06:16:30PM -0700, Ira Weiny wrote:
> > That might require to support
> > kmap_atomic_prot everywhere first, which sounds like a really good
> > idea anyway, and would avoid the need for strange workaround in drm.
> 
> Having a kmap_atomic_prot() seems like a good idea.  But I'm not exactly sure
> why CONFIG_x86 is being called out specifically in the DRM code?

Probably because it only existed on x86 back then.  And drm has a
tendency of working around core problems with hacks instead of doing
the fairly easy fixups.