From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx156.postini.com [74.125.245.156]) by kanga.kvack.org (Postfix) with SMTP id F27F06B005D for ; Tue, 25 Sep 2012 09:57:30 -0400 (EDT) From: Naoya Horiguchi Subject: [PATCH] pagemap: fix wrong KPF_THP on slab pages Date: Tue, 25 Sep 2012 09:56:54 -0400 Message-Id: <1348581414-19103-1-git-send-email-n-horiguchi@ah.jp.nec.com> Sender: owner-linux-mm@kvack.org List-ID: To: Wu Fengguang , Andrew Morton Cc: KOSAKI Motohiro , Andi Kleen , linux-mm@kvack.org, linux-kernel@vger.kernel.org KPF_THP can be set on non-huge compound pages like slab pages, because PageTransCompound only sees PG_head and PG_tail. Obviously this is a bug and breaks user space applications which look for thp via /proc/kpageflags. Currently thp is constructed only on anonymous pages, so this patch makes KPF_THP be set when both of PageAnon and PageTransCompound are true. Signed-off-by: Naoya Horiguchi --- fs/proc/page.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git v3.6-rc6.orig/fs/proc/page.c v3.6-rc6/fs/proc/page.c index 7fcd0d6..613102d 100644 --- v3.6-rc6.orig/fs/proc/page.c +++ v3.6-rc6/fs/proc/page.c @@ -115,7 +115,7 @@ u64 stable_page_flags(struct page *page) u |= 1 << KPF_COMPOUND_TAIL; if (PageHuge(page)) u |= 1 << KPF_HUGE; - else if (PageTransCompound(page)) + else if (PageTransCompound(page) && PageAnon(page)) u |= 1 << KPF_THP; /* -- 1.7.11.4 -- 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