From: Mika Båtsman mika.batsman@gmail.com

Probe of dvb_usb_gl861 was working at least with v4.4. Noticed the issue with v4.13 but according to similar issues the problem started with v4.9.

[ 15.288065] transfer buffer not dma capable [ 15.288090] WARNING: CPU: 2 PID: 493 at drivers/usb/core/hcd.c:1595 usb_hcd_map_urb_for_dma+0x4e2/0x640 ...CUT... [ 15.288791] dvb_usb_gl861: probe of 3-7:1.0 failed with error -5

Tested with MSI Mega Sky 580 DVB-T Tuner [GL861]

Cc: stable@vger.kernel.org Signed-off-by: Mika Båtsman mika.batsman@gmail.com --- drivers/media/usb/dvb-usb-v2/gl861.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/drivers/media/usb/dvb-usb-v2/gl861.c b/drivers/media/usb/dvb-usb-v2/gl861.c index b1b09c5..0a988e3 100644 --- a/drivers/media/usb/dvb-usb-v2/gl861.c +++ b/drivers/media/usb/dvb-usb-v2/gl861.c @@ -20,15 +20,22 @@ static int gl861_i2c_msg(struct dvb_usb_device *d, u8 addr, u16 value = addr << (8 + 1); int wo = (rbuf == NULL || rlen == 0); /* write-only */ u8 req, type; + int ret; + void *dmadata;

if (wo) { req = GL861_REQ_I2C_WRITE; type = GL861_WRITE; + dmadata = kmemdup(wbuf, wlen, GFP_KERNEL); } else { /* rw */ req = GL861_REQ_I2C_READ; type = GL861_READ; + dmadata = kmalloc(rlen, GFP_KERNEL); }

+ if (!dmadata) + return -ENOMEM; + switch (wlen) { case 1: index = wbuf[0]; @@ -45,8 +52,14 @@ static int gl861_i2c_msg(struct dvb_usb_device *d, u8 addr,

msleep(1); /* avoid I2C errors */

- return usb_control_msg(d->udev, usb_rcvctrlpipe(d->udev, 0), req, type, - value, index, rbuf, rlen, 2000); + ret = usb_control_msg(d->udev, usb_rcvctrlpipe(d->udev, 0), req, type, + value, index, dmadata, rlen, 2000); + + if (!wo) + memcpy(rbuf, dmadata, rlen); + + kfree(dmadata); + return ret; }

/* I2C */