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Date: Wed, 01 Jul 2015 14:07:12 +0100
From: Marc Zyngier <marc.zyngier@arm.com>
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To: Christoffer Dall <christoffer.dall@linaro.org>,
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CC: Steve Capper <steve.capper@linaro.org>,
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Subject: Re: [PATCH] arm64: Don't report clear pmds and puds as huge
References: <1435752511-7079-1-git-send-email-christoffer.dall@linaro.org>
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On 01/07/15 13:08, Christoffer Dall wrote:
> The current pmd_huge() and pud_huge() functions simply check if the table
> bit is not set and reports the entries as huge in that case.  This is
> counter-intuitive as a clear pmd/pud cannot also be a huge pmd/pud, and
> it is inconsistent with at least arm and x86.
> 
> To prevent others from making the same mistake as me in looking at code
> that calls these functions and to fix an issue with KVM on arm64 that
> causes memory corruption due to incorrect page reference counting
> resulting from this mistake, let's change the behavior.
> 
> Cc: stable@vger.kernel.org
> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>

FWIW:

Acked-by: Marc Zyngier <marc.zyngier@arm.com>

	M.
-- 
Jazz is not dead. It just smells funny...