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Date: Thu, 4 Apr 2024 08:24:04 -0300
From: Jason Gunthorpe <jgg@nvidia.com>
To: Peter Xu <peterx@redhat.com>
Cc: Nathan Chancellor <nathan@kernel.org>, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org, Yang Shi <shy828301@gmail.com>,
	"Kirill A . Shutemov" <kirill@shutemov.name>,
	Mike Kravetz <mike.kravetz@oracle.com>,
	John Hubbard <jhubbard@nvidia.com>,
	Michael Ellerman <mpe@ellerman.id.au>,
	Andrew Jones <andrew.jones@linux.dev>,
	Muchun Song <muchun.song@linux.dev>,
	linux-riscv@lists.infradead.org, linuxppc-dev@lists.ozlabs.org,
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	Mike Rapoport <rppt@kernel.org>,
	Axel Rasmussen <axelrasmussen@google.com>,
	Huacai Chen <chenhuacai@kernel.org>,
	WANG Xuerui <kernel@xen0n.name>, loongarch@lists.linux.dev
Subject: Re: [PATCH v4 05/13] mm/arch: Provide pud_pfn() fallback
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On Wed, Apr 03, 2024 at 02:25:20PM -0400, Peter Xu wrote:

> > I'd say the BUILD_BUG has done it's job and found an issue, fix it by
> > not defining pud_leaf? I don't see any calls to pud_leaf in loongarch
> > at least
> 
> Yes, that sounds better too to me, however it means we may also risk other
> archs that can fail another defconfig build.. and I worry I bring trouble
> to multiple such cases.  Fundamentally it's indeed my patch that broke
> those builds, so I still sent the change and leave that for arch developers
> to decide the best for the archs.

But your change causes silent data corruption if the code path is
run.. I think we are overall better to wade through the compile time
bugs from linux-next. Honestly if there were alot then I'd think there
would be more complaints already.

Maybe it should just be a seperate step from this series.

Jason