Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756001AbZDPFzK (ORCPT ); Thu, 16 Apr 2009 01:55:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755518AbZDPFym (ORCPT ); Thu, 16 Apr 2009 01:54:42 -0400 Received: from outbound.icp-qv1-irony-out2.iinet.net.au ([203.59.1.107]:64070 "EHLO outbound.icp-qv1-irony-out2.iinet.net.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755521AbZDPFyl (ORCPT ); Thu, 16 Apr 2009 01:54:41 -0400 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: ArgBAJxk5kl8qNY8/2dsb2JhbAAI0BuDfQY X-IronPort-AV: E=Sophos;i="4.40,197,1238947200"; d="scan'208";a="467881295" Subject: [PATCH 1/9] ipu_idmac: Use disable_irq_nosync() from within irq handlers. From: Ben Nizette To: dan.j.williams@intel.com Cc: linux-kernel Content-Type: text/plain Date: Thu, 16 Apr 2009 15:54:12 +1000 Message-Id: <1239861252.29831.114.camel@linux-51e8.site> Mime-Version: 1.0 X-Mailer: Evolution 2.22.1.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1435 Lines: 44 disable_irq() should wait for all running handlers to complete before returning. As such, if it's used to disable an interrupt from that interrupt's handler it will deadlock. This replaces the dangerous instances with the _nosync() variant which doesn't have this problem. Note the 2 handlers in question are only used #ifdef DEBUG so I imagine these code paths don't get hit often. Signed-off-by: Ben Nizette --- diff --git a/drivers/dma/ipu/ipu_idmac.c b/drivers/dma/ipu/ipu_idmac.c index e202a6c..3a4deea 100644 --- a/drivers/dma/ipu/ipu_idmac.c +++ b/drivers/dma/ipu/ipu_idmac.c @@ -1547,7 +1547,7 @@ static irqreturn_t ic_sof_irq(int irq, void *dev_id) struct idmac_channel *ichan = dev_id; printk(KERN_DEBUG "Got SOF IRQ %d on Channel %d\n", irq, ichan->dma_chan.chan_id); - disable_irq(irq); + disable_irq_nosync(irq); return IRQ_HANDLED; } @@ -1556,7 +1556,7 @@ static irqreturn_t ic_eof_irq(int irq, void *dev_id) struct idmac_channel *ichan = dev_id; printk(KERN_DEBUG "Got EOF IRQ %d on Channel %d\n", irq, ichan->dma_chan.chan_id); - disable_irq(irq); + disable_irq_nosync(irq); return IRQ_HANDLED; } -- 1.6.0.2 -- 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/