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Message-ID: <1406617244.4935.81.camel@pasglop>
Subject: Re: [PATCH] powerpc: thp: Add write barrier after updating the
 valid bit
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Date: Tue, 29 Jul 2014 17:00:44 +1000
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On Tue, 2014-07-29 at 12:25 +0530, Aneesh Kumar K.V wrote:
> We want to make sure for usage like below we don't reorder the  load.
> 
> if (pmd_trans_huge(*pmdp)){
> 
>    get_hpte_slot_array(pmdp)
> }

Shouldn't we also make sure that we don't have lock set ? (In case it's
in the middle of being updated).

Cheers,
Ben.