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=-11.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 0BE49C63777 for ; Mon, 30 Nov 2020 03:30:06 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 75B4920663 for ; Mon, 30 Nov 2020 03:30:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 75B4920663 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 7A3DD6B0036; Sun, 29 Nov 2020 22:30:04 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 72CA06B005D; Sun, 29 Nov 2020 22:30:04 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5F4356B0068; Sun, 29 Nov 2020 22:30:04 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0090.hostedemail.com [216.40.44.90]) by kanga.kvack.org (Postfix) with ESMTP id 45B9C6B0036 for ; Sun, 29 Nov 2020 22:30:04 -0500 (EST) Received: from smtpin13.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 02B9F363B for ; Mon, 30 Nov 2020 03:30:03 +0000 (UTC) X-FDA: 77539655928.13.bait00_1c17fd12739e Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin13.hostedemail.com (Postfix) with ESMTP id CE9EE18140B69 for ; Mon, 30 Nov 2020 03:30:03 +0000 (UTC) X-HE-Tag: bait00_1c17fd12739e X-Filterd-Recvd-Size: 4030 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf16.hostedemail.com (Postfix) with ESMTP for ; Mon, 30 Nov 2020 03:30:03 +0000 (UTC) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 17C6C30E; Sun, 29 Nov 2020 19:30:02 -0800 (PST) Received: from p8cg001049571a15.arm.com (unknown [10.163.84.86]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 344A73F23F; Sun, 29 Nov 2020 19:29:57 -0800 (PST) From: Anshuman Khandual To: linux-mm@kvack.org, akpm@linux-foundation.org, david@redhat.com Cc: linux-arm-kernel@lists.infradead.org, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, Anshuman Khandual , Heiko Carstens , Vasily Gorbik , Catalin Marinas , Will Deacon , Ard Biesheuvel , Mark Rutland Subject: [RFC V2 0/3] mm/hotplug: Pre-validate the address range with platform Date: Mon, 30 Nov 2020 08:59:49 +0530 Message-Id: <1606706992-26656-1-git-send-email-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.7.4 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: This series adds a mechanism allowing platforms to weigh in and prevalidate incoming address range before proceeding further with the memory hotplug. This helps prevent potential platform errors for the given address range, down the hotplug call chain, which inevitably fails the hotplug itself. This mechanism was suggested by David Hildenbrand during another discussion with respect to a memory hotplug fix on arm64 platform. https://lore.kernel.org/linux-arm-kernel/1600332402-30123-1-git-send-email-anshuman.khandual@arm.com/ This mechanism focuses on the addressibility aspect and not [sub] section alignment aspect. Hence check_hotplug_memory_range() and check_pfn_span() have been left unchanged. Wondering if all these can still be unified in an expanded memhp_range_allowed() check, that can be called from multiple memory hot add and remove paths. This series applies on v5.10-rc6 and has been slightly tested on arm64. But looking for some early feedback here. Changes in RFC V2: Incorporated all review feedbacks from David. - Added additional range check in __segment_load() on s390 which was lost - Changed is_private init in pagemap_range() - Moved the framework into mm/memory_hotplug.c - Made arch_get_addressable_range() a __weak function - Renamed arch_get_addressable_range() as arch_get_mappable_range() - Callback arch_get_mappable_range() only handles range requiring linear mapping - Merged multiple memhp_range_allowed() checks in register_memory_resource() - Replaced WARN() with pr_warn() in memhp_range_allowed() - Replaced error return code ERANGE with E2BIG Changes in RFC V1: https://lore.kernel.org/linux-mm/1606098529-7907-1-git-send-email-anshuman.khandual@arm.com/ Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Catalin Marinas Cc: Will Deacon Cc: Ard Biesheuvel Cc: Mark Rutland Cc: David Hildenbrand Cc: Andrew Morton Cc: linux-arm-kernel@lists.infradead.org Cc: linux-s390@vger.kernel.org Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org Anshuman Khandual (3): mm/hotplug: Prevalidate the address range being added with platform arm64/mm: Define arch_get_mappable_range() s390/mm: Define arch_get_mappable_range() arch/arm64/mm/mmu.c | 14 +++---- arch/s390/mm/extmem.c | 5 +++ arch/s390/mm/vmem.c | 13 ++++-- include/linux/memory_hotplug.h | 2 + mm/memory_hotplug.c | 77 +++++++++++++++++++++++++--------- mm/memremap.c | 6 ++- 6 files changed, 84 insertions(+), 33 deletions(-) -- 2.20.1