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=-16.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 78F7FC433ED for ; Tue, 11 May 2021 10:26:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 42C5261933 for ; Tue, 11 May 2021 10:26:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231459AbhEKK1m (ORCPT ); Tue, 11 May 2021 06:27:42 -0400 Received: from mail.kernel.org ([198.145.29.99]:33668 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231340AbhEKK12 (ORCPT ); Tue, 11 May 2021 06:27:28 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 29BA26192C for ; Tue, 11 May 2021 10:26:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1620728782; bh=95zZVK7qfIh+tOUiU4moyxlDwWV95Vmvl6IczEmpWaQ=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=jB28dGoEQZhWVX4kG3NoWMrOUOJqKxtGnVTy20zjRDxZSYi5HDoH9X4KG04ToeloA cDtUs47l0amh5owyQHo9Y71oQ4LjdMeLKiJKekCv6EqMBcFAvE6kFY+zLTpnzK2c02 7NweGlJAUMef4+eX+40tudEHBQhgb9TWfDjReYJgblgVGGMr9/GmZ/91vitXEd782t g9xjaa2eZafJ5DzGUi2oT6AyQqRubnfU9TEwg5H9ElYCJfxuOahiwURSuGFYl4ZES1 rQXX3sG+FHbaG+SB1zpITPkwnC4j3iSe7CdYaT/+XuyT3ovBDEvX1eDXOge37ZUbm5 6GXvX4c06Mn7w== Received: by mail-ot1-f47.google.com with SMTP id g15-20020a9d128f0000b02902a7d7a7bb6eso17061856otg.9 for ; Tue, 11 May 2021 03:26:22 -0700 (PDT) X-Gm-Message-State: AOAM533HyY+13MQi9DpLVqSBLVR5wEJgsb5C/LRAHGTgH5C5Etmx5SBW rnLG14elyAXaitk8hbE7bgF2xI/lYdnvvm4p15M= X-Google-Smtp-Source: ABdhPJx7OAWZjUg75AH1MONFkX/rKqoEq6W+l0O8JhjgsRoszXYlOPWDD3ytFXdgmlzvdYrIN3iUwS6soQhwbypE0Tw= X-Received: by 2002:a9d:7cd8:: with SMTP id r24mr13558179otn.90.1620728781371; Tue, 11 May 2021 03:26:21 -0700 (PDT) MIME-Version: 1.0 References: <20210511100550.28178-1-rppt@kernel.org> <20210511100550.28178-5-rppt@kernel.org> In-Reply-To: <20210511100550.28178-5-rppt@kernel.org> From: Ard Biesheuvel Date: Tue, 11 May 2021 12:26:10 +0200 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v4 4/4] arm64: drop pfn_valid_within() and simplify pfn_valid() To: Mike Rapoport Cc: Andrew Morton , Anshuman Khandual , Catalin Marinas , David Hildenbrand , Marc Zyngier , Mark Rutland , Mike Rapoport , Will Deacon , kvmarm , Linux ARM , Linux Kernel Mailing List , Linux Memory Management List Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 11 May 2021 at 12:06, Mike Rapoport wrote: > > From: Mike Rapoport > > The arm64's version of pfn_valid() differs from the generic because of two > reasons: > > * Parts of the memory map are freed during boot. This makes it necessary to > verify that there is actual physical memory that corresponds to a pfn > which is done by querying memblock. > > * There are NOMAP memory regions. These regions are not mapped in the > linear map and until the previous commit the struct pages representing > these areas had default values. > > As the consequence of absence of the special treatment of NOMAP regions in > the memory map it was necessary to use memblock_is_map_memory() in > pfn_valid() and to have pfn_valid_within() aliased to pfn_valid() so that > generic mm functionality would not treat a NOMAP page as a normal page. > > Since the NOMAP regions are now marked as PageReserved(), pfn walkers and > the rest of core mm will treat them as unusable memory and thus > pfn_valid_within() is no longer required at all and can be disabled by > removing CONFIG_HOLES_IN_ZONE on arm64. > > pfn_valid() can be slightly simplified by replacing > memblock_is_map_memory() with memblock_is_memory(). > > Signed-off-by: Mike Rapoport > Acked-by: David Hildenbrand Acked-by: Ard Biesheuvel ... and many thanks for cleaning this up. > --- > arch/arm64/Kconfig | 3 --- > arch/arm64/mm/init.c | 2 +- > 2 files changed, 1 insertion(+), 4 deletions(-) > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > index 9f1d8566bbf9..d7dc8698cf8e 100644 > --- a/arch/arm64/Kconfig > +++ b/arch/arm64/Kconfig > @@ -1052,9 +1052,6 @@ config NEED_PER_CPU_EMBED_FIRST_CHUNK > def_bool y > depends on NUMA > > -config HOLES_IN_ZONE > - def_bool y > - > source "kernel/Kconfig.hz" > > config ARCH_SPARSEMEM_ENABLE > diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c > index 798f74f501d5..fb07218da2c0 100644 > --- a/arch/arm64/mm/init.c > +++ b/arch/arm64/mm/init.c > @@ -251,7 +251,7 @@ int pfn_valid(unsigned long pfn) > if (!early_section(ms)) > return pfn_section_valid(ms, pfn); > > - return memblock_is_map_memory(addr); > + return memblock_is_memory(addr); > } > EXPORT_SYMBOL(pfn_valid); > > -- > 2.28.0 >