From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:46276 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730784AbeLKP5S (ORCPT ); Tue, 11 Dec 2018 10:57:18 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lucas Stach , Robin Gong , Vinod Koul Subject: [PATCH 4.19 084/118] Revert "dmaengine: imx-sdma: alloclate bd memory from dma pool" Date: Tue, 11 Dec 2018 16:41:43 +0100 Message-Id: <20181211151647.662325438@linuxfoundation.org> In-Reply-To: <20181211151644.216668863@linuxfoundation.org> References: <20181211151644.216668863@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Lucas Stach commit ebb853b1bd5f659b92c71dc6a9de44cfc37c78c0 upstream. This reverts commit fe5b85c656bc. The SDMA engine needs the descriptors to be contiguous in memory. As the dma pool API is only able to provide a single descriptor per alloc invocation there is no guarantee that multiple descriptors satisfy this requirement. Also the code in question is broken as it only allocates memory for a single descriptor, without looking at the number of descriptors required for the transfer, leading to out-of-bounds accesses when the descriptors are written. Signed-off-by: Lucas Stach Signed-off-by: Robin Gong Cc: stable Signed-off-by: Vinod Koul Signed-off-by: Greg Kroah-Hartman --- drivers/dma/imx-sdma.c | 18 ++++++------------ 1 file changed, 6 insertions(+), 12 deletions(-) --- a/drivers/dma/imx-sdma.c +++ b/drivers/dma/imx-sdma.c @@ -24,7 +24,6 @@ #include #include #include -#include #include #include #include @@ -376,7 +375,6 @@ struct sdma_channel { u32 shp_addr, per_addr; enum dma_status status; struct imx_dma_data data; - struct dma_pool *bd_pool; }; #define IMX_DMA_SG_LOOP BIT(0) @@ -1192,10 +1190,11 @@ out: static int sdma_alloc_bd(struct sdma_desc *desc) { + u32 bd_size = desc->num_bd * sizeof(struct sdma_buffer_descriptor); int ret = 0; - desc->bd = dma_pool_alloc(desc->sdmac->bd_pool, GFP_ATOMIC, - &desc->bd_phys); + desc->bd = dma_zalloc_coherent(NULL, bd_size, &desc->bd_phys, + GFP_ATOMIC); if (!desc->bd) { ret = -ENOMEM; goto out; @@ -1206,7 +1205,9 @@ out: static void sdma_free_bd(struct sdma_desc *desc) { - dma_pool_free(desc->sdmac->bd_pool, desc->bd, desc->bd_phys); + u32 bd_size = desc->num_bd * sizeof(struct sdma_buffer_descriptor); + + dma_free_coherent(NULL, bd_size, desc->bd, desc->bd_phys); } static void sdma_desc_free(struct virt_dma_desc *vd) @@ -1272,10 +1273,6 @@ static int sdma_alloc_chan_resources(str if (ret) goto disable_clk_ahb; - sdmac->bd_pool = dma_pool_create("bd_pool", chan->device->dev, - sizeof(struct sdma_buffer_descriptor), - 32, 0); - return 0; disable_clk_ahb: @@ -1304,9 +1301,6 @@ static void sdma_free_chan_resources(str clk_disable(sdma->clk_ipg); clk_disable(sdma->clk_ahb); - - dma_pool_destroy(sdmac->bd_pool); - sdmac->bd_pool = NULL; } static struct sdma_desc *sdma_transfer_init(struct sdma_channel *sdmac,