From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from foss.arm.com ([217.140.110.172]:54420 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725885AbgLCANf (ORCPT ); Wed, 2 Dec 2020 19:13:35 -0500 Subject: Re: [RFC V2 0/3] mm/hotplug: Pre-validate the address range with platform References: <1606706992-26656-1-git-send-email-anshuman.khandual@arm.com> <20201202203540.GC11274@osiris> From: Anshuman Khandual Message-ID: <2d2a947f-3c4f-6106-583a-7da4e757a7aa@arm.com> Date: Thu, 3 Dec 2020 05:42:35 +0530 MIME-Version: 1.0 In-Reply-To: <20201202203540.GC11274@osiris> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit List-ID: To: Heiko Carstens Cc: linux-mm@kvack.org, akpm@linux-foundation.org, david@redhat.com, linux-arm-kernel@lists.infradead.org, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, Vasily Gorbik , Catalin Marinas , Will Deacon , Ard Biesheuvel , Mark Rutland On 12/3/20 2:05 AM, Heiko Carstens wrote: > On Mon, Nov 30, 2020 at 08:59:49AM +0530, Anshuman Khandual wrote: >> 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 > > Btw. please use git send-email's --cc-cover option to make sure that > all patches of this series will be sent to all listed cc's. > I really dislike to receive only the cover-letter and maybe on patch > and then have to figure out where to find the rest. Okay, will ensure that. > > Thanks :) >