From mboxrd@z Thu Jan  1 00:00:00 1970
From: linux@arm.linux.org.uk (Russell King - ARM Linux)
Date: Fri, 21 Feb 2014 11:28:12 +0000
Subject: [RFC PATCH 2/2] arm: mm: Double logical invert for LPAE
 pte_write(), pte_dirty()
In-Reply-To: <1392396913-13570-3-git-send-email-steve.capper@linaro.org>
References: <1392396913-13570-1-git-send-email-steve.capper@linaro.org>
 <1392396913-13570-3-git-send-email-steve.capper@linaro.org>
Message-ID: <20140221112812.GC21483@n2100.arm.linux.org.uk>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Fri, Feb 14, 2014 at 04:55:13PM +0000, Steve Capper wrote:
> On LPAE, L_PTE_WRITE and L_PTE_DIRTY are in the upper 32-bits.
> Unfortunately, results from pte_write() and pte_dirty() are downcast
> to 32-bits by core code:
>   o gather_stats
>   o huge_pte_dirty
>   o huge_pte_write
>   o make_migration_entry
> 
> This patch adds a double logical invert to pte_write() and pte_dirty()
> for LPAE to ensure that the lower 32-bits are set if true.

We should ensure all those functions return something which is compatible
with "int" correctly.  It didn't matter for non-LPAE as the PTEs fit in
32-bit, but with LPAE, that really needs fixing independently of your
other patch.

-- 
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