From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932675Ab1LPJCF (ORCPT ); Fri, 16 Dec 2011 04:02:05 -0500 Received: from mga01.intel.com ([192.55.52.88]:27690 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760220Ab1LPJBs (ORCPT ); Fri, 16 Dec 2011 04:01:48 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.71,315,1320652800"; d="scan'208";a="102886137" From: Adrian Hunter To: Vinod Koul Cc: Dan Williams , LKML , Adrian Hunter Subject: [PATCH 1/3] dmaengine: intel_mid_dma: locking and freeing fixes Date: Fri, 16 Dec 2011 11:01:38 +0200 Message-Id: <1324026100-3124-2-git-send-email-adrian.hunter@intel.com> X-Mailer: git-send-email 1.7.6.4 In-Reply-To: <1324026100-3124-1-git-send-email-adrian.hunter@intel.com> References: <1324026100-3124-1-git-send-email-adrian.hunter@intel.com> Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Two issues are fixed: 1. DMA descriptors are reused so when freeing lli structures that are linked to them, the pointer must be nulled. 2. midc_scan_descriptors() must be called with the channel lock held. Signed-off-by: Adrian Hunter --- drivers/dma/intel_mid_dma.c | 7 ++++++- 1 files changed, 6 insertions(+), 1 deletions(-) diff --git a/drivers/dma/intel_mid_dma.c b/drivers/dma/intel_mid_dma.c index 01929ed..d4b9616 100644 --- a/drivers/dma/intel_mid_dma.c +++ b/drivers/dma/intel_mid_dma.c @@ -280,7 +280,8 @@ static void midc_dostart(struct intel_mid_dma_chan *midc, * callbacks but must be called with the lock held. */ static void midc_descriptor_complete(struct intel_mid_dma_chan *midc, - struct intel_mid_dma_desc *desc) + struct intel_mid_dma_desc *desc) + __releases(&midc->lock) __acquires(&midc->lock) { struct dma_async_tx_descriptor *txd = &desc->txd; dma_async_tx_callback callback_txd = NULL; @@ -311,6 +312,7 @@ static void midc_descriptor_complete(struct intel_mid_dma_chan *midc, pci_pool_free(desc->lli_pool, desc->lli, desc->lli_phys); pci_pool_destroy(desc->lli_pool); + desc->lli = NULL; } list_move(&desc->desc_node, &midc->free_list); midc->busy = false; @@ -490,7 +492,9 @@ static enum dma_status intel_mid_dma_tx_status(struct dma_chan *chan, ret = dma_async_is_complete(cookie, last_complete, last_used); if (ret != DMA_SUCCESS) { + spin_lock_bh(&midc->lock); midc_scan_descriptors(to_middma_device(chan->device), midc); + spin_unlock_bh(&midc->lock); last_complete = midc->completed; last_used = chan->cookie; @@ -566,6 +570,7 @@ static int intel_mid_dma_device_control(struct dma_chan *chan, pci_pool_free(desc->lli_pool, desc->lli, desc->lli_phys); pci_pool_destroy(desc->lli_pool); + desc->lli = NULL; } list_move(&desc->desc_node, &midc->free_list); } -- 1.7.6.4