Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934556AbZIEAUd (ORCPT ); Fri, 4 Sep 2009 20:20:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S934499AbZIEAUa (ORCPT ); Fri, 4 Sep 2009 20:20:30 -0400 Received: from kroah.org ([198.145.64.141]:42040 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934193AbZIEAU2 (ORCPT ); Fri, 4 Sep 2009 20:20:28 -0400 X-Mailbox-Line: From gregkh@mini.kroah.org Fri Sep 4 17:14:47 2009 Message-Id: <20090905001447.228488853@mini.kroah.org> User-Agent: quilt/0.48-1 Date: Fri, 04 Sep 2009 17:13:37 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Guillaume Knispel , Thomas Gleixner , Tejun Heo Subject: [patch 02/71] poll/select: initialize triggered field of struct poll_wqueues References: <20090905001335.106974681@mini.kroah.org> Content-Disposition: inline; filename=poll-select-initialize-triggered-field-of-struct-poll_wqueues.patch In-Reply-To: <20090905001824.GA18171@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1731 Lines: 40 2.6.30-stable review patch. If anyone has any objections, please let us know. ------------------ From: Guillaume Knispel commit b2add73dbf93fd50f00564d7abc3e2b9aa9dd20c upstream. The triggered field of struct poll_wqueues introduced in commit 5f820f648c92a5ecc771a96b3c29aa6e90013bba ("poll: allow f_op->poll to sleep"). It was first set to 1 in pollwake() (now __pollwake() ), tested and later set to 0 in poll_schedule_timeout(), but not initialized before. As a result when the process needs to sleep, triggered was likely to be non-zero even if pollwake() is not called before the first poll_schedule_timeout(), meaning schedule_hrtimeout_range() would not be called and an extra loop calling all ->poll() would be done. This patch initialize triggered to 0 in poll_initwait() so the ->poll() are not called twice before the process goes to sleep when it needs to. Signed-off-by: Guillaume Knispel Acked-by: Thomas Gleixner Acked-by: Tejun Heo Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- fs/select.c | 1 + 1 file changed, 1 insertion(+) --- a/fs/select.c +++ b/fs/select.c @@ -110,6 +110,7 @@ void poll_initwait(struct poll_wqueues * { init_poll_funcptr(&pwq->pt, __pollwait); pwq->polling_task = current; + pwq->triggered = 0; pwq->error = 0; pwq->table = NULL; pwq->inline_index = 0; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/