[PATCH 3.2 069/152] USB: serial: mos7840: fix non-atomic allocation in write path

[Ben Hutchings]

3.2.84-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Alexey Khoroshilov <khoroshilov@xxxxxxxxx>

commit 3b7c7e52efda0d4640060de747768360ba70a7c0 upstream.

There is an allocation with GFP_KERNEL flag in mos7840_write(),
while it may be called from interrupt context.

Follow-up for commit 191252837626 ("USB: kobil_sct: fix non-atomic
allocation in write path")

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@xxxxxxxxx>
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/usb/serial/mos7840.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/usb/serial/mos7840.c
+++ b/drivers/usb/serial/mos7840.c
@@ -1524,8 +1524,8 @@ static int mos7840_write(struct tty_stru
 	}
 
 	if (urb->transfer_buffer == NULL) {
-		urb->transfer_buffer =
-		    kmalloc(URB_TRANSFER_BUFFER_SIZE, GFP_KERNEL);
+		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
+					       GFP_ATOMIC);
 
 		if (urb->transfer_buffer == NULL) {
 			dev_err(&port->dev, "%s no more kernel memory...\n",