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Date: Mon, 20 May 2024 19:42:26 +0200
From: Oscar Salvador <osalvador@suse.de>
To: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Michael Ellerman <mpe@ellerman.id.au>,
	Andrew Morton <akpm@linux-foundation.org>,
	Jason Gunthorpe <jgg@nvidia.com>, Peter Xu <peterx@redhat.com>,
	Nicholas Piggin <npiggin@gmail.com>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"linux-mm@kvack.org" <linux-mm@kvack.org>,
	"linuxppc-dev@lists.ozlabs.org" <linuxppc-dev@lists.ozlabs.org>
Subject: Re: [RFC PATCH v2 06/20] powerpc/8xx: Fix size given to
 set_huge_pte_at()
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On Mon, May 20, 2024 at 04:31:39PM +0000, Christophe Leroy wrote:
> Hi Oscar, hi Michael,
> 
> Le 20/05/2024 ? 11:14, Oscar Salvador a ?crit?:
> > On Fri, May 17, 2024 at 09:00:00PM +0200, Christophe Leroy wrote:
> >> set_huge_pte_at() expects the real page size, not the psize which is
> > 
> > "expects the size of the huge page" sounds bettter?
> 
> Parameter 'pzize' already provides the size of the hugepage, but not in 
> the way set_huge_pte_at() expects it.
> 
> psize has one of the values defined by MMU_PAGE_XXX macros defined in 
> arch/powerpc/include/asm/mmu.h while set_huge_pte_at() expects the size 
> as a value.

Yes, psize is an index, which is not a size by itself but used to get
mmu_psize_def.shift to see the actual size, I guess.
This is why I thought that being explicit about "expects the size of the
huge page" was better.

But no strong feelings here.


-- 
Oscar Salvador
SUSE Labs