From patchwork Wed Jan 16 15:56:36 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [196/222] rtlwifi: fix incorrect use of usb_alloc_coherent with usb_control_msg From: Herton Ronaldo Krzesinski X-Patchwork-Id: 212769 Message-Id: <1358351822-7675-197-git-send-email-herton.krzesinski@canonical.com> To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Jussi Kivilinna Date: Wed, 16 Jan 2013 13:56:36 -0200 3.5.7.3 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Jussi Kivilinna commit 4c3de5920c486b8eefa6187ee6a181864c161100 upstream. Incorrect use of usb_alloc_coherent memory as input buffer to usb_control_msg can cause problems in arch DMA code, for example kernel BUG at 'arch/arm/include/asm/dma-mapping.h:321' on ARM (linux-3.4). Change _usb_writeN_sync use kmalloc'd buffer instead. Signed-off-by: Jussi Kivilinna Acked-by: Larry Finger Signed-off-by: John W. Linville Signed-off-by: Herton Ronaldo Krzesinski --- drivers/net/wireless/rtlwifi/usb.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/net/wireless/rtlwifi/usb.c b/drivers/net/wireless/rtlwifi/usb.c index aa970fc..8fa144f 100644 --- a/drivers/net/wireless/rtlwifi/usb.c +++ b/drivers/net/wireless/rtlwifi/usb.c @@ -210,17 +210,16 @@ static void _usb_writeN_sync(struct rtl_priv *rtlpriv, u32 addr, void *data, u16 index = REALTEK_USB_VENQT_CMD_IDX; int pipe = usb_sndctrlpipe(udev, 0); /* write_out */ u8 *buffer; - dma_addr_t dma_addr; - wvalue = (u16)(addr&0x0000ffff); - buffer = usb_alloc_coherent(udev, (size_t)len, GFP_ATOMIC, &dma_addr); + wvalue = (u16)(addr & 0x0000ffff); + buffer = kmalloc(len, GFP_ATOMIC); if (!buffer) return; memcpy(buffer, data, len); usb_control_msg(udev, pipe, request, reqtype, wvalue, index, buffer, len, 50); - usb_free_coherent(udev, (size_t)len, buffer, dma_addr); + kfree(buffer); } static void _rtl_usb_io_handler_init(struct device *dev,