Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S937348AbdCJNbQ (ORCPT ); Fri, 10 Mar 2017 08:31:16 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:43609 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934443AbdCJLwb (ORCPT ); Fri, 10 Mar 2017 06:52:31 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Mauro Carvalho Chehab" Date: Fri, 10 Mar 2017 11:46:23 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 299/370] [media] siano: make it work again with CONFIG_VMAP_STACK In-Reply-To: X-SA-Exim-Connect-IP: 82.70.136.246 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2187 Lines: 67 3.16.42-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Mauro Carvalho Chehab commit f9c85ee67164b37f9296eab3b754e543e4e96a1c upstream. Reported as a Kaffeine bug: https://bugs.kde.org/show_bug.cgi?id=375811 The USB control messages require DMA to work. We cannot pass a stack-allocated buffer, as it is not warranted that the stack would be into a DMA enabled area. On Kernel 4.9, the default is to not accept DMA on stack anymore on x86 architecture. On other architectures, this has been a requirement since Kernel 2.2. So, after this patch, this driver should likely work fine on all archs. Tested with USB ID 2040:5510: Hauppauge Windham Signed-off-by: Mauro Carvalho Chehab [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings --- drivers/media/usb/siano/smsusb.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) --- a/drivers/media/usb/siano/smsusb.c +++ b/drivers/media/usb/siano/smsusb.c @@ -206,22 +206,30 @@ static int smsusb_start_streaming(struct static int smsusb_sendrequest(void *context, void *buffer, size_t size) { struct smsusb_device_t *dev = (struct smsusb_device_t *) context; - struct sms_msg_hdr *phdr = (struct sms_msg_hdr *) buffer; - int dummy; + struct sms_msg_hdr *phdr; + int dummy, ret; if (dev->state != SMSUSB_ACTIVE) { sms_debug("Device not active yet"); return -ENOENT; } + phdr = kmalloc(size, GFP_KERNEL); + if (!phdr) + return -ENOMEM; + memcpy(phdr, buffer, size); + sms_debug("sending %s(%d) size: %d", smscore_translate_msg(phdr->msg_type), phdr->msg_type, phdr->msg_length); smsendian_handle_tx_message((struct sms_msg_data *) phdr); - smsendian_handle_message_header((struct sms_msg_hdr *)buffer); - return usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, 2), - buffer, size, &dummy, 1000); + smsendian_handle_message_header((struct sms_msg_hdr *)phdr); + ret = usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, 2), + phdr, size, &dummy, 1000); + + kfree(phdr); + return ret; } static char *smsusb1_fw_lkup[] = {