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[23.128.96.18]) by mx.google.com with ESMTP id ka25si34644921ejc.354.2021.07.23.05.08.14; Fri, 23 Jul 2021 05:08:38 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@ellerman.id.au header.s=201909 header.b=VunPNjPI; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234751AbhGWLXv (ORCPT + 99 others); Fri, 23 Jul 2021 07:23:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58490 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234385AbhGWLXu (ORCPT ); Fri, 23 Jul 2021 07:23:50 -0400 Received: from ozlabs.org (bilbo.ozlabs.org [IPv6:2401:3900:2:1::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5B75FC061575 for ; Fri, 23 Jul 2021 05:04:24 -0700 (PDT) Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4GWSfR5Vqtz9sXM; Fri, 23 Jul 2021 22:04:15 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ellerman.id.au; s=201909; t=1627041861; bh=WEE70A1SmlcnlIsv9nVnRGPp1lz7FMXEUMxrnsgf+IU=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=VunPNjPI5UTxmlZmtF6HnK+D0Dif1lwUaNWcXlVbCnOy3zlfgpBXZRcdGvCjeSpTD 9GtJzMFZAjmswf1Hvf+Shhuu3DtNGBXMNTQoMka2kFXjYcF/zGbOVaCZOBpwbNaHMV epX/8JSDuS2F3jGKGPdB1wvzULNj0TkI4wo+Z5qZ8TF2KuuqLjMk0XTObjG1udah19 U1CpdO9KIVSiwPBast1gIEWa3fuADmNkO9j6lepWMRmuG+MHxyeWmwMTljc1HY+qcN iPuTprU1H6rO2uX1bsNbdVNf6qs+BaSKB5njML9F9aEsaaPNMQrnX9vJgFwZ5rtJUH 0p1oAfMTFZbgA== From: Michael Ellerman To: Will Deacon , Christophe Leroy Cc: catalin.marinas@arm.com, kernel-team@android.com, Will Deacon , Thomas Gleixner , linuxppc-dev@lists.ozlabs.org, Mark Rutland , Benjamin Herrenschmidt , Geert Uytterhoeven , Andrew Morton , Mike Rapoport , Ard Biesheuvel , linux-arm-kernel@lists.infradead.org, Paul Mackerras , Jonathan Marek , linux-kernel@vger.kernel.org, Marc Zyngier , Nicholas Piggin Subject: Re: [PATCH v2] Revert "mm/pgtable: add stubs for {pmd/pub}_{set/clear}_huge" In-Reply-To: <162686329170.980657.905966885675716231.b4-ty@kernel.org> References: <20210720202627.Horde.vlszNhxkKrLIg0-3Sn2ucw5@messagerie.c-s.fr> <87r1fs1762.fsf@mpe.ellerman.id.au> <162686329170.980657.905966885675716231.b4-ty@kernel.org> Date: Fri, 23 Jul 2021 22:04:10 +1000 Message-ID: <87o8at1bk5.fsf@mpe.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Will Deacon writes: > 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. No worries, thanks to Christophe for identifying the solution while on vacation! Beers seem a long way off, but hopefully one day :) cheers