From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta8.messagelabs.com (mail6.bemta8.messagelabs.com [216.82.243.55]) by kanga.kvack.org (Postfix) with ESMTP id 4FA699000BD for ; Mon, 20 Jun 2011 17:10:31 -0400 (EDT) Date: Mon, 20 Jun 2011 16:10:28 -0500 (CDT) From: Christoph Lameter Subject: Re: [Bugme-new] [Bug 37072] New: Random BUG at include/linux/swapops.h:105 In-Reply-To: <20110620135353.cfe979ae.akpm@linux-foundation.org> Message-ID: References: <20110620135353.cfe979ae.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: bugme-daemon@bugzilla.kernel.org, linux-mm@kvack.org, luke-jr+linuxbugs@utopios.org On Mon, 20 Jun 2011, Andrew Morton wrote: > handle_mm_fault > ->handle_pte_fault > ->do_swap_page > ->migration_entry_wait > ->migration_entry_to_page > ->BUG_ON(!PageLocked(p)) > > How is this supposed to ever work? A page is always locked during migration. Thus a migration entry can only exist while a page is locked. The migration entries purpose is to hold off establishing new references to a page that is locked. See unmap_and_move(). Looks like some of the recent patches may cause an unlock the page without removal of the migration entry? -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org