From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx2-b.sourceforge.net ([10.3.1.92] helo=mail.sourceforge.net) by sc8-sf-list1-new.sourceforge.net with esmtp (Exim 4.43) id 1InJj7-0005Xm-JF for user-mode-linux-devel@lists.sourceforge.net; Wed, 31 Oct 2007 12:59:45 -0700 Received: from [198.99.130.12] (helo=saraswathi.solana.com) by mail.sourceforge.net with esmtps (TLSv1:AES256-SHA:256) (Exim 4.44) id 1InJj7-00054J-0a for user-mode-linux-devel@lists.sourceforge.net; Wed, 31 Oct 2007 12:59:45 -0700 Date: Wed, 31 Oct 2007 15:59:38 -0400 From: Jeff Dike Message-ID: <20071031195938.GA9630@c2.user-mode-linux.org> Mime-Version: 1.0 Content-Disposition: inline Subject: [uml-devel] [PATCH 1/4] UML - Fix spurious IRQ testing 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: Andrew Morton Cc: LKML , uml-devel The spurious IRQ testing in request_irq is mishandled in um_request_irq, which sets the incoming file descriptors non-blocking only after request_irq succeeds. This results in the spurious irq calling read on a blocking descriptor, and a hang. Fixed by reversing the O_NONBLOCK setting and the request_irq call. Signed-off-by: Jeff Dike --- arch/um/kernel/irq.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) Index: linux-2.6.22/arch/um/kernel/irq.c =================================================================== --- linux-2.6.22.orig/arch/um/kernel/irq.c 2007-10-25 12:23:09.000000000 -0400 +++ linux-2.6.22/arch/um/kernel/irq.c 2007-10-29 13:00:18.000000000 -0400 @@ -347,14 +347,15 @@ int um_request_irq(unsigned int irq, int { int err; - err = request_irq(irq, handler, irqflags, devname, dev_id); - if (err) - return err; - - if (fd != -1) + if (fd != -1) { err = activate_fd(irq, fd, type, dev_id); - return err; + if (err) + return err; + } + + return request_irq(irq, handler, irqflags, devname, dev_id); } + EXPORT_SYMBOL(um_request_irq); EXPORT_SYMBOL(reactivate_fd); ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755016AbXJaUBL (ORCPT ); Wed, 31 Oct 2007 16:01:11 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759480AbXJaUAA (ORCPT ); Wed, 31 Oct 2007 16:00:00 -0400 Received: from saraswathi.solana.com ([198.99.130.12]:48817 "EHLO saraswathi.solana.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754168AbXJaT77 (ORCPT ); Wed, 31 Oct 2007 15:59:59 -0400 Date: Wed, 31 Oct 2007 15:59:38 -0400 From: Jeff Dike To: Andrew Morton Cc: LKML , uml-devel Subject: [PATCH 1/4] UML - Fix spurious IRQ testing Message-ID: <20071031195938.GA9630@c2.user-mode-linux.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.4.2.3i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org The spurious IRQ testing in request_irq is mishandled in um_request_irq, which sets the incoming file descriptors non-blocking only after request_irq succeeds. This results in the spurious irq calling read on a blocking descriptor, and a hang. Fixed by reversing the O_NONBLOCK setting and the request_irq call. Signed-off-by: Jeff Dike --- arch/um/kernel/irq.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) Index: linux-2.6.22/arch/um/kernel/irq.c =================================================================== --- linux-2.6.22.orig/arch/um/kernel/irq.c 2007-10-25 12:23:09.000000000 -0400 +++ linux-2.6.22/arch/um/kernel/irq.c 2007-10-29 13:00:18.000000000 -0400 @@ -347,14 +347,15 @@ int um_request_irq(unsigned int irq, int { int err; - err = request_irq(irq, handler, irqflags, devname, dev_id); - if (err) - return err; - - if (fd != -1) + if (fd != -1) { err = activate_fd(irq, fd, type, dev_id); - return err; + if (err) + return err; + } + + return request_irq(irq, handler, irqflags, devname, dev_id); } + EXPORT_SYMBOL(um_request_irq); EXPORT_SYMBOL(reactivate_fd);