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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 46711C32753 for ; Wed, 14 Aug 2019 15:41:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1A9B42054F for ; Wed, 14 Aug 2019 15:41:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728230AbfHNPl1 (ORCPT ); Wed, 14 Aug 2019 11:41:27 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59718 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728152AbfHNPlY (ORCPT ); Wed, 14 Aug 2019 11:41:24 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 788F88E592; Wed, 14 Aug 2019 15:41:24 +0000 (UTC) Received: from t460s.redhat.com (ovpn-116-49.ams2.redhat.com [10.36.116.49]) by smtp.corp.redhat.com (Postfix) with ESMTP id A234E80693; Wed, 14 Aug 2019 15:41:22 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, David Hildenbrand , Arun KS , Andrew Morton , Oscar Salvador , Michal Hocko , Pavel Tatashin , Dan Williams Subject: [PATCH v2 4/5] mm/memory_hotplug: Make sure the pfn is aligned to the order when onlining Date: Wed, 14 Aug 2019 17:41:08 +0200 Message-Id: <20190814154109.3448-5-david@redhat.com> In-Reply-To: <20190814154109.3448-1-david@redhat.com> References: <20190814154109.3448-1-david@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Wed, 14 Aug 2019 15:41:24 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit a9cd410a3d29 ("mm/page_alloc.c: memory hotplug: free pages as higher order") assumed that any PFN we get via memory resources is aligned to to MAX_ORDER - 1, I am not convinced that is always true. Let's play safe, check the alignment and fallback to single pages. Cc: Arun KS Cc: Andrew Morton Cc: Oscar Salvador Cc: Michal Hocko Cc: Pavel Tatashin Cc: Dan Williams Signed-off-by: David Hildenbrand --- mm/memory_hotplug.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 63b1775f7cf8..f245fb50ba7f 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -646,6 +646,9 @@ static int online_pages_range(unsigned long start_pfn, unsigned long nr_pages, */ for (pfn = start_pfn; pfn < end_pfn; pfn += 1ul << order) { order = min(MAX_ORDER - 1, get_order(PFN_PHYS(end_pfn - pfn))); + /* __free_pages_core() wants pfns to be aligned to the order */ + if (unlikely(!IS_ALIGNED(pfn, 1ul << order))) + order = 0; (*online_page_callback)(pfn_to_page(pfn), order); } -- 2.21.0