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Subject: Re: [PATCH V2 19/31] powerpc/mm: Convert 4k hash insert to C
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Anshuman Khandual <khandual@linux.vnet.ibm.com>, "Aneesh Kumar K.V"
 <aneesh.kumar@linux.vnet.ibm.com>, paulus@samba.org, mpe@ellerman.id.au
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Date: Thu, 01 Oct 2015 06:18:18 +1000
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On Wed, 2015-09-30 at 17:37 +0530, Anshuman Khandual wrote:
> > +             if (unlikely(old_pte & _PAGE_BUSY))
> > +                     return 0;
> > +             /* If PTE permissions don't match, take page fault */
> 
> We are already in page fault interrupt path,  will it be better
> if we call it "take Linux page fault" instead as we will go back
> walking the page table.

A better wording would be "escalate the page fault"

Cheers,
Ben.