From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9BBD8C7619F for ; Mon, 17 Feb 2020 10:16:39 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 5C1B920725 for ; Mon, 17 Feb 2020 10:16:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="Eq5UfpAp" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5C1B920725 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id EA3866B0005; Mon, 17 Feb 2020 05:16:38 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id E4D216B0006; Mon, 17 Feb 2020 05:16:38 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D1B4A6B0007; Mon, 17 Feb 2020 05:16:38 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0079.hostedemail.com [216.40.44.79]) by kanga.kvack.org (Postfix) with ESMTP id B6FD06B0005 for ; Mon, 17 Feb 2020 05:16:38 -0500 (EST) Received: from smtpin13.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 6B82A1EF3 for ; Mon, 17 Feb 2020 10:16:38 +0000 (UTC) X-FDA: 76499214876.13.meat11_5702ebe055e49 X-HE-Tag: meat11_5702ebe055e49 X-Filterd-Recvd-Size: 4489 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf50.hostedemail.com (Postfix) with ESMTP for ; Mon, 17 Feb 2020 10:16:37 +0000 (UTC) Received: from mail-wm1-f48.google.com (mail-wm1-f48.google.com [209.85.128.48]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id CC66B22525 for ; Mon, 17 Feb 2020 10:16:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581934597; bh=4cLlQS6dh3TII+e63aZc4SI9thiBfzKMd7Iu5QCGWjs=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=Eq5UfpApFfSqgahMtWpRHuyClv3jPdyyd6PVRbQT2PcAXEEpHt8JYkGsEBXaLUR3v yxJfKOj8zQKAAWslqWAgPnGkbIgTkaVY05SWCFX3Pd+3Z/SEFcQhj2cEaKl35qQJv3 QGWBAbZxg7TlwdUTdJuvsq13UzOI6Ya/rYQgLfwE= Received: by mail-wm1-f48.google.com with SMTP id s144so7008448wme.1 for ; Mon, 17 Feb 2020 02:16:36 -0800 (PST) X-Gm-Message-State: APjAAAVBeYqG5/F1ZTwBokWXvNvdsOfpKId2/+GL31COFLNzXqBcyLz6 4aLSD0aCsPn74PnIv0xX7q0XyM+SWV3C0Ra3L41LZA== X-Google-Smtp-Source: APXvYqzqZNxl118rnsQ1j1OXjhkx9vVcOI+aj/V8YvXdxCexJjSRKnmYAijbWYByC/Tq0yzU4F9Fp8tfyDdGHA9vZD0= X-Received: by 2002:a1c:b603:: with SMTP id g3mr22636081wmf.133.1581934595070; Mon, 17 Feb 2020 02:16:35 -0800 (PST) MIME-Version: 1.0 References: <20191218162402.45610-1-steven.price@arm.com> <20191218162402.45610-22-steven.price@arm.com> In-Reply-To: From: Ard Biesheuvel Date: Mon, 17 Feb 2020 11:16:23 +0100 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v17 21/23] arm64: mm: Convert mm/dump.c to use walk_page_range() To: Steven Price Cc: Andrew Morton , Linux-MM , Andy Lutomirski , Arnd Bergmann , Borislav Petkov , Catalin Marinas , Dave Hansen , Ingo Molnar , James Morse , =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= , Peter Zijlstra , Thomas Gleixner , Will Deacon , "the arch/x86 maintainers" , "H. Peter Anvin" , linux-arm-kernel , Linux Kernel Mailing List , Mark Rutland , "Liang, Kan" Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, 17 Feb 2020 at 11:01, Steven Price wrote: > > On 16/02/2020 16:25, Ard Biesheuvel wrote: > > On Wed, 18 Dec 2019 at 17:25, Steven Price wrote: > >> > >> Now walk_page_range() can walk kernel page tables, we can switch the > >> arm64 ptdump code over to using it, simplifying the code. > >> > >> Reviewed-by: Catalin Marinas > >> Signed-off-by: Steven Price > > > > I did not realize this at the time, but this patch removes the ability > > to dump the EFI page tables on 32-bit ARM. Was that intentional? > > No that wasn't intentional, but I can't instantly see how this change > affects 32-bit ARM. > > > >> diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c > >> index 899b803842bb..9dda2602c862 100644 > >> --- a/drivers/firmware/efi/arm-runtime.c > >> +++ b/drivers/firmware/efi/arm-runtime.c > >> @@ -27,7 +27,7 @@ > >> > >> extern u64 efi_system_table; > >> > >> -#ifdef CONFIG_ARM64_PTDUMP_DEBUGFS > >> +#if defined(CONFIG_PTDUMP_DEBUGFS) && defined(CONFIG_ARM64) > > The previous define was *ARM64* so should never have been true when > building for arm. The new condition should be equivalent (arm64 && > ptdump enabled). > > Am I missing something? > Not at all, I just got confused. IIRC we did have support for dumping the EFI pages tables on 32-bit ARM at *some* point, but it obviously wasn't your patch that removed it. Apologies for the noise.