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From:   Will Deacon <will@kernel.org>
To:     Christophe Leroy <christophe.leroy@csgroup.eu>,
        Michael Ellerman <mpe@ellerman.id.au>
Cc:     catalin.marinas@arm.com, kernel-team@android.com,
        Will Deacon <will@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        linuxppc-dev@lists.ozlabs.org, Mark Rutland <mark.rutland@arm.com>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Mike Rapoport <rppt@kernel.org>,
        Ard Biesheuvel <ardb@kernel.org>,
        linux-arm-kernel@lists.infradead.org,
        Paul Mackerras <paulus@samba.org>,
        Jonathan Marek <jonathan@marek.ca>,
        linux-kernel@vger.kernel.org, Marc Zyngier <maz@kernel.org>,
        Nicholas Piggin <npiggin@gmail.com>
Subject: Re: [PATCH v2] Revert "mm/pgtable: add stubs for {pmd/pub}_{set/clear}_huge"
Date:   Wed, 21 Jul 2021 11:47:53 +0100
Message-Id: <162686329170.980657.905966885675716231.b4-ty@kernel.org>
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On Wed, 21 Jul 2021 17:02:13 +1000, Michael Ellerman wrote:
> This reverts commit c742199a014de23ee92055c2473d91fe5561ffdf.
> 
> c742199a014d ("mm/pgtable: add stubs for {pmd/pub}_{set/clear}_huge")
> breaks arm64 in at least two ways for configurations where PUD or PMD
> folding occur:
> 
>   1. We no longer install huge-vmap mappings and silently fall back to
>      page-granular entries, despite being able to install block entries
>      at what is effectively the PGD level.
> 
> [...]

Thank you Michael! I owe you a beer next time I see you, if we don't go
extinct before then.

Applied to arm64 (for-next/fixes), thanks!

[1/1] Revert "mm/pgtable: add stubs for {pmd/pub}_{set/clear}_huge"
      https://git.kernel.org/arm64/c/d8a719059b9d

Cheers,
-- 
Will

https://fixes.arm64.dev
https://next.arm64.dev
https://will.arm64.dev