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. Tested with USB ID 2040:5510: Hauppauge Windham Cc: stable@xxxxxxxxxxxxxxx # For 4.9+ Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx> --- drivers/media/usb/siano/smsusb.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) diff --git a/drivers/media/usb/siano/smsusb.c b/drivers/media/usb/siano/smsusb.c index a4dcaec31d02..8c1f926567ec 100644 --- a/drivers/media/usb/siano/smsusb.c +++ b/drivers/media/usb/siano/smsusb.c @@ -218,22 +218,30 @@ static int smsusb_start_streaming(struct smsusb_device_t *dev) 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) { pr_debug("Device not active yet\n"); return -ENOENT; } + phdr = kmalloc(size, GFP_KERNEL); + if (!phdr) + return -ENOMEM; + memcpy(phdr, buffer, size); + pr_debug("sending %s(%d) size: %d\n", 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[] = { -- 2.9.3
