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=-5.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 311A5C433E0 for ; Tue, 19 Jan 2021 12:23:30 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B2C1022D2A for ; Tue, 19 Jan 2021 12:23:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B2C1022D2A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=ZyoSE3b1JZzMtV4CUzlMPJxmE3t2APotgXpN7PD2Ek8=; b=bfGuJWyatFasIdFA7iKWVO4fD jvVuPpzOol8nbpTqScKCfLBM94PlnyaWRFI5a8Vl1Eqbi7fAGea6n7/fbrZ1j8VNKUA5NdOrdVzL0 Fy6bug7cCJdovUzhN69TVbWaRB4Ugy8M6L55rVFJWG2ydxKjGvrkN+b34rMk/DT4LcKdDOSlFXXv+ 6QkLqtQf2UlfPsNqb3pXusW+wfv8xsrxl5bGjr1T9WRxBVvD2A2bqN/Q6enI/XvEzb55mBBVpNlbo 0UR/Czd6aYSv11DWKqE4PM4JUPCFqFwB17nI8475/9C+vgyy4eEFkFayDKflG5Vue5TSJe8UiqtgR N+wEFCd5w==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l1q1R-0000pC-0B; Tue, 19 Jan 2021 12:22:09 +0000 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1l1q1N-0000oO-89 for linux-arm-kernel@lists.infradead.org; Tue, 19 Jan 2021 12:22:06 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1611058923; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=N/Ldn6cKgGuq/aEJMSquo67YjjGGoJdj7Dnv+qTpdTU=; b=hwdlTP8LY5sFWZybNB2xS3x11OzRtgxfiEaPPKbaPIbi/Gy/cyJ6bSRWaPh8H7HgUgdTId y3TBnXtTHTbGGsAz+wmX8Tqntz38nPbv2gvlY9u9wviBbkCc2ZceN7KxUh+qokTHbOnm6p XrLh8WsAAUOZU7USJ38hmU+B7U/3hnM= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-419-IRQ3jEvWNeCuH6cJJWotVg-1; Tue, 19 Jan 2021 07:21:59 -0500 X-MC-Unique: IRQ3jEvWNeCuH6cJJWotVg-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 137AC107ACE8; Tue, 19 Jan 2021 12:21:57 +0000 (UTC) Received: from [10.36.114.143] (ovpn-114-143.ams2.redhat.com [10.36.114.143]) by smtp.corp.redhat.com (Postfix) with ESMTP id 671E260BF1; Tue, 19 Jan 2021 12:21:54 +0000 (UTC) Subject: Re: [PATCH V3 1/3] mm/memory_hotplug: Prevalidate the address range being added with platform To: Anshuman Khandual , linux-mm@kvack.org, akpm@linux-foundation.org, hca@linux.ibm.com, catalin.marinas@arm.com References: <1610975582-12646-1-git-send-email-anshuman.khandual@arm.com> <1610975582-12646-2-git-send-email-anshuman.khandual@arm.com> From: David Hildenbrand Organization: Red Hat GmbH Message-ID: <691872bb-b251-83e0-126e-afd54683c83e@redhat.com> Date: Tue, 19 Jan 2021 13:21:53 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.5.0 MIME-Version: 1.0 In-Reply-To: <1610975582-12646-2-git-send-email-anshuman.khandual@arm.com> Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210119_072205_339358_102AEFFE X-CRM114-Status: GOOD ( 17.60 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , linux-s390@vger.kernel.org, Vasily Gorbik , linux-kernel@vger.kernel.org, Will Deacon , Ard Biesheuvel , linux-arm-kernel@lists.infradead.org, Oscar Salvador Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 18.01.21 14:12, Anshuman Khandual wrote: > This introduces memhp_range_allowed() which can be called in various memory > hotplug paths to prevalidate the address range which is being added, with > the platform. Then memhp_range_allowed() calls memhp_get_pluggable_range() > which provides applicable address range depending on whether linear mapping > is required or not. For ranges that require linear mapping, it calls a new > arch callback arch_get_mappable_range() which the platform can override. So > the new callback, in turn provides the platform an opportunity to configure > acceptable memory hotplug address ranges in case there are constraints. > > This mechanism will help prevent platform specific errors deep down during > hotplug calls. This drops now redundant check_hotplug_memory_addressable() > check in __add_pages() but instead adds a VM_BUG_ON() check which would In this patch, you keep the __add_pages() checks. But as discussed, we could perform it in mm/memremap.c:pagemap_range() insted and convert it to a VM_BUG_ON(). Apart from that looks good to me. -- Thanks, David / dhildenb _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel