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=-12.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 10BDEC43464 for ; Mon, 21 Sep 2020 12:06:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C8F872193E for ; Mon, 21 Sep 2020 12:06:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726641AbgIUMGD (ORCPT ); Mon, 21 Sep 2020 08:06:03 -0400 Received: from foss.arm.com ([217.140.110.172]:42026 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726355AbgIUMGD (ORCPT ); Mon, 21 Sep 2020 08:06:03 -0400 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 537151063; Mon, 21 Sep 2020 05:06:02 -0700 (PDT) Received: from p8cg001049571a15.arm.com (unknown [10.163.75.158]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id C06B93F73B; Mon, 21 Sep 2020 05:05:58 -0700 (PDT) From: Anshuman Khandual To: linux-arm-kernel@lists.infradead.org Cc: catalin.marinas@arm.com, will@kernel.org, Anshuman Khandual , Will Deacon , Mark Rutland , Marc Zyngier , Steve Capper , Mark Brown , linux-kernel@vger.kernel.org Subject: [PATCH V3 1/3] arm64/mm/hotplug: Register boot memory hot remove notifier earlier Date: Mon, 21 Sep 2020 17:35:06 +0530 Message-Id: <1600689908-28213-2-git-send-email-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1600689908-28213-1-git-send-email-anshuman.khandual@arm.com> References: <1600689908-28213-1-git-send-email-anshuman.khandual@arm.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This moves memory notifier registration earlier in the boot process from device_initcall() to early_initcall() which will help in guarding against potential early boot memory offline requests. Even though there should not be any actual offlinig requests till memory block devices are initialized with memory_dev_init() but then generic init sequence might just change in future. Hence an early registration for the memory event notifier would be helpful. While here, just skip the registration if CONFIG_MEMORY_HOTREMOVE is not enabled and also call out when memory notifier registration fails. Cc: Catalin Marinas Cc: Will Deacon Cc: Mark Rutland Cc: Marc Zyngier Cc: Steve Capper Cc: Mark Brown Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual --- arch/arm64/mm/mmu.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 75df62fea1b6..df3b7415b128 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -1499,7 +1499,17 @@ static struct notifier_block prevent_bootmem_remove_nb = { static int __init prevent_bootmem_remove_init(void) { - return register_memory_notifier(&prevent_bootmem_remove_nb); + int ret = 0; + + if (!IS_ENABLED(CONFIG_MEMORY_HOTREMOVE)) + return ret; + + ret = register_memory_notifier(&prevent_bootmem_remove_nb); + if (!ret) + return ret; + + pr_err("Notifier registration failed - boot memory can be removed\n"); + return ret; } -device_initcall(prevent_bootmem_remove_init); +early_initcall(prevent_bootmem_remove_init); #endif -- 2.20.1