Date: Thu, 17 Dec 2009 10:17:03 -0800 (PST)
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Russell King <rmk+lkml@arm.linux.org.uk>
cc: Christoph Hellwig <hch@infradead.org>, tytso@mit.edu,
       Kyle McMartin <kyle@mcmartin.ca>, linux-parisc@vger.kernel.org,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       James.Bottomley@suse.de, linux-arch@vger.kernel.org,
       Jens Axboe <jens.axboe@oracle.com>
Subject: Re: [git patches] xfs and block fixes for virtually indexed arches
In-Reply-To: <20091217180802.GA1546@flint.arm.linux.org.uk>
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On Thu, 17 Dec 2009, Russell King wrote:
> 
> That's not entirely true.  If you have write back caches which are not DMA
> coherent, you need to as a minimum:
> 
> - on write, clean the cache to ensure that the page is up to date with data
>   held in cache.
> 
> - on read, you must ensure that there are no potential write-backs before
>   the read commenses and invalidate at some point.

Right you are.

		Linus
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