[media] m920x: get rid of on-stack dma buffers

usb_control_msg initiates (and waits for completion of) a dma transfer using
the supplied buffer. That buffer thus has to be seperately allocated on
the heap.

In lib/dma_debug.c the function check_for_stack even warns about it:
	WARNING: at lib/dma-debug.c:866 check_for_stack

Note: This change is tested to compile only, as I don't have the hardware.

Signed-off-by: Florian Mickler <florian@mickler.org>
Cc: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 22 insertions, 11 deletions

diff --git a/drivers/media/dvb/dvb-usb/m920x.c b/drivers/media/dvb/dvb-usb/m920x.c
index 51bfd42387c..9456792f219 100644
--- a/drivers/media/dvb/dvb-usb/m920x.c
+++ b/drivers/media/dvb/dvb-usb/m920x.c
@@ -134,13 +134,17 @@ static int m920x_rc_query(struct dvb_usb_device *d, u32 *event, int *state)
 {
         struct m920x_state *m = d->priv;
         int i, ret = 0;
-        u8 rc_state[2];
+        u8 *rc_state;
+
+        rc_state = kmalloc(2, GFP_KERNEL);
+        if (!rc_state)
+                return -ENOMEM;
 
         if ((ret = m920x_read(d->udev, M9206_CORE, 0x0, M9206_RC_STATE, rc_state, 1)) != 0)
-                goto unlock;
+                goto out;
 
         if ((ret = m920x_read(d->udev, M9206_CORE, 0x0, M9206_RC_KEY, rc_state + 1, 1)) != 0)
-                goto unlock;
+                goto out;
 
         for (i = 0; i < d->props.rc.legacy.rc_map_size; i++)
                 if (rc5_data(&d->props.rc.legacy.rc_map_table[i]) == rc_state[1]) {
@@ -149,7 +153,7 @@ static int m920x_rc_query(struct dvb_usb_device *d, u32 *event, int *state)
                         switch(rc_state[0]) {
                         case 0x80:
                                 *state = REMOTE_NO_KEY_PRESSED;
-                                goto unlock;
+                                goto out;
 
                         case 0x88: /* framing error or "invalid code" */
                         case 0x99:
@@ -157,7 +161,7 @@ static int m920x_rc_query(struct dvb_usb_device *d, u32 *event, int *state)
                         case 0xd8:
                                 *state = REMOTE_NO_KEY_PRESSED;
                                 m->rep_count = 0;
-                                goto unlock;
+                                goto out;
 
                         case 0x93:
                         case 0x92:
@@ -165,7 +169,7 @@ static int m920x_rc_query(struct dvb_usb_device *d, u32 *event, int *state)
                         case 0x82:
                                 m->rep_count = 0;
                                 *state = REMOTE_KEY_PRESSED;
-                                goto unlock;
+                                goto out;
 
                         case 0x91:
                         case 0x81: /* pinnacle PCTV310e */
@@ -174,12 +178,12 @@ static int m920x_rc_query(struct dvb_usb_device *d, u32 *event, int *state)
                                         *state = REMOTE_KEY_REPEAT;
                                 else
                                         *state = REMOTE_NO_KEY_PRESSED;
-                                goto unlock;
+                                goto out;
 
                         default:
                                 deb("Unexpected rc state %02x\n", rc_state[0]);
                                 *state = REMOTE_NO_KEY_PRESSED;
-                                goto unlock;
+                                goto out;
                         }
                 }
 
@@ -188,8 +192,8 @@ static int m920x_rc_query(struct dvb_usb_device *d, u32 *event, int *state)
 
         *state = REMOTE_NO_KEY_PRESSED;
 
- unlock:
-
+ out:
+        kfree(rc_state);
         return ret;
 }
 
@@ -339,13 +343,19 @@ static int m920x_pid_filter(struct dvb_usb_adapter *adap, int index, u16 pid, in
 static int m920x_firmware_download(struct usb_device *udev, const struct firmware *fw)
 {
         u16 value, index, size;
-        u8 read[4], *buff;
+        u8 *read, *buff;
         int i, pass, ret = 0;
 
         buff = kmalloc(65536, GFP_KERNEL);
         if (buff == NULL)
                 return -ENOMEM;
 
+        read = kmalloc(4, GFP_KERNEL);
+        if (!read) {
+                kfree(buff);
+                return -ENOMEM;
+        }
+
         if ((ret = m920x_read(udev, M9206_FILTER, 0x0, 0x8000, read, 4)) != 0)
                 goto done;
         deb("%x %x %x %x\n", read[0], read[1], read[2], read[3]);
@@ -396,6 +406,7 @@ static int m920x_firmware_download(struct usb_device *udev, const struct firmwar
         deb("firmware uploaded!\n");
 
  done:
+        kfree(read);
         kfree(buff);
 
         return ret;