Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751262AbXBZLwP (ORCPT ); Mon, 26 Feb 2007 06:52:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751275AbXBZLwP (ORCPT ); Mon, 26 Feb 2007 06:52:15 -0500 Received: from mail.screens.ru ([213.234.233.54]:51055 "EHLO mail.screens.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751262AbXBZLwO (ORCPT ); Mon, 26 Feb 2007 06:52:14 -0500 Date: Mon, 26 Feb 2007 14:52:16 +0300 From: Oleg Nesterov To: "Rafael J. Wysocki" Cc: LKML , Andrew Morton , Pavel Machek , Srivatsa Vaddagiri , Aneesh Kumar , "Paul E. McKenney" , Gautham R Shenoy Subject: Re: [RFC][PATCH 3/3] Freezer: Prevent ___call_usermodehelper from missing freezing requests Message-ID: <20070226115216.GA234@tv-sign.ru> References: <200702261139.59130.rjw@sisk.pl> <200702261152.18379.rjw@sisk.pl> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200702261152.18379.rjw@sisk.pl> User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1790 Lines: 48 On 02/26, Rafael J. Wysocki wrote: > > NOTE: Alternatively, we can just drop flush_signals() from there, but I'm not > sure that's the right thing to do. We should drop it, I believe. I forgot to send a patch. Oleg. > --- > From: Rafael J. Wysocki > > Since ____call_usermodehelper() calls flush_signals(current), the task that > enters it may miss a freezing request. However, if ____call_usermodehelper() > clears TIF_FREEZE for the current task after flush_signals(current) returns, the > freezer will generate one more freezing request for this task. > > Signed-off-by: Rafael J. Wysocki > --- > kernel/kmod.c | 2 ++ > 1 file changed, 2 insertions(+) > > Index: linux-2.6.20-mm2/kernel/kmod.c > =================================================================== > --- linux-2.6.20-mm2.orig/kernel/kmod.c 2007-02-25 12:07:15.000000000 +0100 > +++ linux-2.6.20-mm2/kernel/kmod.c 2007-02-25 12:49:16.000000000 +0100 > @@ -34,6 +34,7 @@ > #include > #include > #include > +#include > #include > > extern int delete_module(const char *name, unsigned int flags); > @@ -258,6 +259,7 @@ static int ____call_usermodehelper(void > new_session = key_get(sub_info->ring); > flush_signals(current); > spin_lock_irq(¤t->sighand->siglock); > + do_not_freeze(current); > old_session = __install_session_keyring(current, new_session); > flush_signal_handlers(current, 1); > sigemptyset(¤t->blocked); - 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/