From mboxrd@z Thu Jan  1 00:00:00 1970
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: [CFT] MM: Pass a PTE pointer to update_mmu_cache() rather than
 the PTE itself
Date: Fri, 22 Jan 2010 14:50:19 +1100
Message-ID: <1264132219.3601.28.camel@pasglop>
References: <20100120135202.GA20937@flint.arm.linux.org.uk>
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To: Russell King <rmk+lkml@arm.linux.org.uk>
Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org

On Wed, 2010-01-20 at 13:52 +0000, Russell King wrote:
> On VIVT ARM, when we have multiple shared mappings of the same file
> in the same MM, we need to ensure that we have coherency across all
> copies.  We do this via make_coherent() by making the pages
> uncacheable.
> 
> This used to work fine, until we allowed highmem with highpte - we
> now have a page table which is mapped as required, and is not available
> for modification via update_mmu_cache().

Looks good. I'll test when I'm back from LCA.

Cheers,
Ben.