Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754245Ab1CUSeJ (ORCPT ); Mon, 21 Mar 2011 14:34:09 -0400 Received: from ist.d-labs.de ([213.239.218.44]:43651 "EHLO mx01.d-labs.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751161Ab1CUSeG (ORCPT ); Mon, 21 Mar 2011 14:34:06 -0400 From: Florian Mickler To: mchehab@infradead.org Cc: linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, js@linuxtv.org, tskd2@yahoo.co.jp, liplianin@me.by, g.marco@freenet.de, aet@rasterburn.org, pb@linuxtv.org, mkrufky@linuxtv.org, nick@nick-andrew.net, max@veneto.com, janne-dvb@grunau.be, Florian Mickler Subject: [PATCH 4/6] [media] dw2102: get rid of on-stack dma buffer Date: Mon, 21 Mar 2011 19:33:44 +0100 Message-Id: <1300732426-18958-5-git-send-email-florian@mickler.org> X-Mailer: git-send-email 1.7.4.1 In-Reply-To: <1300732426-18958-1-git-send-email-florian@mickler.org> References: <1300732426-18958-1-git-send-email-florian@mickler.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1743 Lines: 54 usb_control_msg initiates (and waits for completion of) a dma transfer using the supplied buffer. That buffer thus has to be seperately allocated on the heap. In lib/dma_debug.c the function check_for_stack even warns about it: WARNING: at lib/dma-debug.c:866 check_for_stack Note: This change is tested to compile only, as I don't have the hardware. Signed-off-by: Florian Mickler --- drivers/media/dvb/dvb-usb/dw2102.c | 10 ++++++++-- 1 files changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/media/dvb/dvb-usb/dw2102.c b/drivers/media/dvb/dvb-usb/dw2102.c index 2c307ba..4c8ff39 100644 --- a/drivers/media/dvb/dvb-usb/dw2102.c +++ b/drivers/media/dvb/dvb-usb/dw2102.c @@ -101,12 +101,16 @@ static int dw210x_op_rw(struct usb_device *dev, u8 request, u16 value, u16 index, u8 * data, u16 len, int flags) { int ret; - u8 u8buf[len]; - + u8 *u8buf; unsigned int pipe = (flags == DW210X_READ_MSG) ? usb_rcvctrlpipe(dev, 0) : usb_sndctrlpipe(dev, 0); u8 request_type = (flags == DW210X_READ_MSG) ? USB_DIR_IN : USB_DIR_OUT; + u8buf = kmalloc(len, GFP_KERNEL); + if (!u8buf) + return -ENOMEM; + + if (flags == DW210X_WRITE_MSG) memcpy(u8buf, data, len); ret = usb_control_msg(dev, pipe, request, request_type | USB_TYPE_VENDOR, @@ -114,6 +118,8 @@ static int dw210x_op_rw(struct usb_device *dev, u8 request, u16 value, if (flags == DW210X_READ_MSG) memcpy(data, u8buf, len); + + kfree(u8buf); return ret; } -- 1.7.4.1 -- 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/