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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,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 7FE4EC282CB for ; Fri, 8 Feb 2019 09:06:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 587812147C for ; Fri, 8 Feb 2019 09:06:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727550AbfBHJGZ (ORCPT ); Fri, 8 Feb 2019 04:06:25 -0500 Received: from smtp.nue.novell.com ([195.135.221.5]:35224 "EHLO smtp.nue.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727273AbfBHJGY (ORCPT ); Fri, 8 Feb 2019 04:06:24 -0500 Received: from emea4-mta.ukb.novell.com ([10.120.13.87]) by smtp.nue.novell.com with ESMTP (TLS encrypted); Fri, 08 Feb 2019 10:06:23 +0100 Received: from d104.suse.de (nwb-a10-snat.microfocus.com [10.120.13.202]) by emea4-mta.ukb.novell.com with ESMTP (NOT encrypted); Fri, 08 Feb 2019 09:06:14 +0000 From: Oscar Salvador To: akpm@linux-foundation.org Cc: mhocko@suse.com, david@redhat.com, anthony.yznaga@oracle.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Oscar Salvador Subject: [PATCH] mm,memory_hotplug: Explicitly pass the head to isolate_huge_page Date: Fri, 8 Feb 2019 10:06:04 +0100 Message-Id: <20190208090604.975-1-osalvador@suse.de> X-Mailer: git-send-email 2.13.7 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org isolate_huge_page() expects we pass the head of hugetlb page to it: bool isolate_huge_page(...) { ... VM_BUG_ON_PAGE(!PageHead(page), page); ... } While I really cannot think of any situation where we end up with a non-head page between hands in do_migrate_range(), let us make sure the code is as sane as possible by explicitly passing the Head. Since we already got the pointer, it does not take us extra effort. Signed-off-by: Oscar Salvador --- mm/memory_hotplug.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 656ff386ac15..d5f7afda67db 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1378,12 +1378,12 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn) if (PageHuge(page)) { struct page *head = compound_head(page); - pfn = page_to_pfn(head) + (1< PFN_SECTION_SHIFT) { ret = -EBUSY; break; } - isolate_huge_page(page, &source); + pfn = page_to_pfn(head) + (1<