From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.91] helo=mail.sourceforge.net) by sc8-sf-list1-new.sourceforge.net with esmtp (Exim 4.43) id 1H0RQy-0002xd-Sp for user-mode-linux-devel@lists.sourceforge.net; Fri, 29 Dec 2006 15:46:44 -0800 Received: from [198.99.130.12] (helo=saraswathi.solana.com) by mail.sourceforge.net with esmtps (TLSv1:AES256-SHA:256) (Exim 4.44) id 1H0RQy-0007gz-4h for user-mode-linux-devel@lists.sourceforge.net; Fri, 29 Dec 2006 15:46:44 -0800 Message-Id: <200612292341.kBTNfUqs005544@ccure.user-mode-linux.org> Mime-Version: 1.0 Date: Fri, 29 Dec 2006 18:41:30 -0500 From: Jeff Dike Subject: [uml-devel] [PATCH 4/6] UML - Lock the irqs_to_free list List-Id: The user-mode Linux development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: user-mode-linux-devel-bounces@lists.sourceforge.net Errors-To: user-mode-linux-devel-bounces@lists.sourceforge.net To: akpm@osdl.org Cc: linux-kernel@vger.kernel.org, user-mode-linux-devel@lists.sourceforge.net Fix (i.e. add some) the locking around the irqs_to_free list. Signed-off-by: Jeff Dike -- arch/um/drivers/chan_kern.c | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-) Index: linux-2.6.18-mm/arch/um/drivers/chan_kern.c =================================================================== --- linux-2.6.18-mm.orig/arch/um/drivers/chan_kern.c 2006-12-29 15:27:16.000000000 -0500 +++ linux-2.6.18-mm/arch/um/drivers/chan_kern.c 2006-12-29 16:38:43.000000000 -0500 @@ -222,15 +222,28 @@ void enable_chan(struct line *line) } } +/* Items are added in IRQ context, when free_irq can't be called, and + * removed in process context, when it can. + * This handles interrupt sources which disappear, and which need to + * be permanently disabled. This is discovered in IRQ context, but + * the freeing of the IRQ must be done later. + */ +static DEFINE_SPINLOCK(irqs_to_free_lock); static LIST_HEAD(irqs_to_free); void free_irqs(void) { struct chan *chan; + LIST_HEAD(list); + struct list_head *ele; + + spin_lock_irq(&irqs_to_free_lock); + list_splice_init(&irqs_to_free, &list); + INIT_LIST_HEAD(&irqs_to_free); + spin_unlock_irq(&irqs_to_free_lock); - while(!list_empty(&irqs_to_free)){ - chan = list_entry(irqs_to_free.next, struct chan, free_list); - list_del(&chan->free_list); + list_for_each(ele, &list){ + chan = list_entry(ele, struct chan, free_list); if(chan->input) free_irq(chan->line->driver->read_irq, chan); @@ -246,7 +259,9 @@ static void close_one_chan(struct chan * return; if(delay_free_irq){ + spin_lock_irq(&irqs_to_free_lock); list_add(&chan->free_list, &irqs_to_free); + spin_unlock_irq(&irqs_to_free_lock); } else { if(chan->input) ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel