From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt0-f199.google.com (mail-qt0-f199.google.com [209.85.216.199]) by kanga.kvack.org (Postfix) with ESMTP id 1DF2E6B0008 for ; Thu, 1 Mar 2018 07:48:54 -0500 (EST) Received: by mail-qt0-f199.google.com with SMTP id c26so4821372qtj.14 for ; Thu, 01 Mar 2018 04:48:54 -0800 (PST) Received: from mx1.redhat.com (mx3-rdu2.redhat.com. [66.187.233.73]) by mx.google.com with ESMTPS id c197si122582qkb.295.2018.03.01.04.48.53 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 01 Mar 2018 04:48:53 -0800 (PST) From: Daniel Vacek Subject: [PATCH] mm/page_alloc: fix memmap_init_zone pageblock alignment Date: Thu, 1 Mar 2018 13:47:45 +0100 Message-Id: <1519908465-12328-1-git-send-email-neelx@redhat.com> Sender: owner-linux-mm@kvack.org List-ID: To: linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: Andrew Morton , Michal Hocko , Vlastimil Babka , Mel Gorman , Pavel Tatashin , Paul Burton , Daniel Vacek , stable@vger.kernel.org In move_freepages() a BUG_ON() can be triggered on uninitialized page structures due to pageblock alignment. Aligning the skipped pfns in memmap_init_zone() the same way as in move_freepages_block() simply fixes those crashes. Fixes: b92df1de5d28 ("[mm] page_alloc: skip over regions of invalid pfns where possible") Signed-off-by: Daniel Vacek Cc: stable@vger.kernel.org --- mm/page_alloc.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index cb416723538f..9edee36e6a74 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5359,9 +5359,14 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, /* * Skip to the pfn preceding the next valid one (or * end_pfn), such that we hit a valid pfn (or end_pfn) - * on our next iteration of the loop. + * on our next iteration of the loop. Note that it needs + * to be pageblock aligned even when the region itself + * is not as move_freepages_block() can shift ahead of + * the valid region but still depends on correct page + * metadata. */ - pfn = memblock_next_valid_pfn(pfn, end_pfn) - 1; + pfn = (memblock_next_valid_pfn(pfn, end_pfn) & + ~(pageblock_nr_pages-1)) - 1; #endif continue; } -- 2.16.2 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org