Re: [PATCH] kvaser_usb: fix "dma on the stack" errors

On 11/23/2012 02:40 PM, Olivier Sobrie wrote:

On Fri, Nov 23, 2012 at 02:30:28PM +0100, Olivier Sobrie wrote:

quoted

The dma buffer given to usb_bulk_msg() must be allocated and not on
the stack.
See Documentation/DMA-API-HOWTO.txt section "What memory is DMA'able?"

Signed-off-by: Olivier Sobrie <redacted>
---
Here is the incremental patch.
Thank you Greg !

Olivier

 drivers/net/can/usb/kvaser_usb.c |  110 ++++++++++++++++++++++++--------------
 1 file changed, 69 insertions(+), 41 deletions(-)

diff --git a/drivers/net/can/usb/kvaser_usb.c b/drivers/net/can/usb/kvaser_usb.c
index 8807bf8..7ac6e82 100644
--- a/drivers/net/can/usb/kvaser_usb.c
+++ b/drivers/net/can/usb/kvaser_usb.c

@@ -421,14 +421,21 @@ end:
 static int kvaser_usb_send_simple_msg(const struct kvaser_usb *dev,
 				      u8 msg_id, int channel)
 {
-	struct kvaser_msg msg = {
-		.len = MSG_HEADER_LEN + sizeof(struct kvaser_msg_simple),
-		.id = msg_id,
-		.u.simple.channel = channel,
-		.u.simple.tid = 0xff,
-	};
-
-	return kvaser_usb_send_msg(dev, &msg);
+	struct kvaser_msg *msg;
+	int rc;
+
+	msg = kmalloc(sizeof(*msg), GFP_KERNEL);
+	if (!msg)
+		return -ENOMEM;
+

Doh! I removed by mistake the line "msg->id = msg_id"... grr

Please send a v2 version of this patch with this problem fixed.

MarcMarc

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