From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <48080B86.7040200@cn.fujitsu.com> Date: Fri, 18 Apr 2008 10:46:30 +0800 From: Shi Weihua MIME-Version: 1.0 Subject: [PATCH] memcgroup: check and initialize page->cgroup in memmap_init_zone References: <48080706.50305@cn.fujitsu.com> <48080930.5090905@cn.fujitsu.com> In-Reply-To: <48080930.5090905@cn.fujitsu.com> Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: akpm@linux-foundation.org Cc: Hiroyuki KAMEZAWA , balbir@linux.vnet.ibm.com, xemul@openvz.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, hugh@veritas.com List-ID: When we test memory controller in Fujitsu PrimeQuest(arch: ia64), the compiled kernel boots failed, the following message occured on the telnet terminal. ------------------------------------- .......... ELILO boot: Uncompressing Linux... done Loading file initrd-2.6.25-rc9-00067-gb87e81e.img...done _ (system freezed) ------------------------------------- We found commit 9442ec9df40d952b0de185ae5638a74970388e01 causes this boot failure by git-bisect. And, we found the following change caused the boot failure. ------------------------------------- @@ -2528,7 +2535,6 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zon set_page_links(page, zone, nid, pfn); init_page_count(page); reset_page_mapcount(page); - page_assign_page_cgroup(page, NULL); SetPageReserved(page); /* ------------------------------------- In this patch, the Author Hugh Dickins said "...memmap_init_zone doesn't need it either, ... Linux assumes pointers in zeroed structures are NULL pointers." But it seems it's not always the case, so we should check and initialize page->cgroup anyways. Signed-off-by: Shi Weihua --- diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 402a504..506d4cf 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2518,6 +2518,7 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, struct page *page; unsigned long end_pfn = start_pfn + size; unsigned long pfn; + void *pc; for (pfn = start_pfn; pfn < end_pfn; pfn++) { /* @@ -2535,6 +2536,9 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, set_page_links(page, zone, nid, pfn); init_page_count(page); reset_page_mapcount(page); + pc = page_get_page_cgroup(page); + if (pc) + page_reset_bad_cgroup(page); SetPageReserved(page); /* -- 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