Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752270AbXBRWUR (ORCPT ); Sun, 18 Feb 2007 17:20:17 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752273AbXBRWUR (ORCPT ); Sun, 18 Feb 2007 17:20:17 -0500 Received: from mail.screens.ru ([213.234.233.54]:39691 "EHLO mail.screens.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752270AbXBRWUP (ORCPT ); Sun, 18 Feb 2007 17:20:15 -0500 Date: Mon, 19 Feb 2007 01:17:37 +0300 From: Oleg Nesterov To: Andrew Morton Cc: "Rafael J. Wysocki" , Pavel Machek , "Paul E. McKenney" , linux-kernel@vger.kernel.org Subject: [PATCH] fix refrigerator() vs thaw_process() race Message-ID: <20070218221737.GA4880@tv-sign.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 904 Lines: 26 refrigerator() can miss a wakeup, "wait event" loop needs a proper memory ordering. Signed-off-by: Oleg Nesterov --- WQ/kernel/power/process.c~WAKE 2007-02-18 22:56:49.000000000 +0300 +++ WQ/kernel/power/process.c 2007-02-19 01:04:26.000000000 +0300 @@ -46,8 +46,10 @@ void refrigerator(void) recalc_sigpending(); /* We sent fake signal, clean it up */ spin_unlock_irq(¤t->sighand->siglock); - while (frozen(current)) { - current->state = TASK_UNINTERRUPTIBLE; + for (;;) { + set_current_state(TASK_UNINTERRUPTIBLE); + if (!frozen(current)) + break; schedule(); } pr_debug("%s left refrigerator\n", current->comm); - 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/