Date: Thu, 9 Sep 2004 09:01:16 -0700
From: "David S. Miller" <davem@davemloft.net>
To: Jens Axboe <axboe@suse.de>
Cc: bzolnier@elka.pw.edu.pl, linux-ide@vger.kernel.org,
       linux-kernel@vger.kernel.org, jgarzik@pobox.com
Subject: Re: [patch][9/9] block: remove bio walking
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On Thu, 9 Sep 2004 17:44:53 +0200
Jens Axboe <axboe@suse.de> wrote:

> On Thu, Sep 09 2004, Russell King wrote:
> > Essentially, kernel PIO writes data into the page cache, and that action
> > may leave data in the CPU's caches.  Since the kernels mappings may not
> > be coherent with mappings in userspace, data written to the kernel
> > mappings may remain in the data cache, and stale data would be visible
> > to user space.
> > 
> > There has been talk about using flush_dcache_page() to resolve
> > this issue, but I'm not sure what the outcome was.  Certainly
> > flush_dcache_page() is supposed to be used before the data in the
> > kernels page cache is read or written.
> 
> Have you ever tested bouncing on arm? It seems to be lacking a
> flush_dcache_page() indeed, how does this look?

This looks like a good fix to me too.
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