From: Robert Lukassen Date: Wed, 16 Mar 2011 11:13:34 +0000 (+0100) Subject: USB: Fix 'bad dma' problem on WDM device disconnect X-Git-Tag: v2.6.32.55~7 X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=dc01426e7f98c1e79bbbb41a991d7d4cf77ac968;p=linux-pvops.git USB: Fix 'bad dma' problem on WDM device disconnect commit 878b753e32ca765cd346a5d3038d630178ec78ff upstream. [ changed s/usb_free_coherent/usb_buffer_free/ for 2.6.32.x] In the WDM class driver a disconnect event leads to calls to usb_free_coherent to put back two USB DMA buffers allocated earlier. The call to usb_free_coherent uses a different size parameter (desc->wMaxCommand) than the corresponding call to usb_alloc_coherent (desc->bMaxPacketSize0). When a disconnect event occurs, this leads to 'bad dma' complaints from usb core because the USB DMA buffer is being pushed back to the 'buffer-2048' pool from which it has not been allocated. This patch against the most recent linux-2.6 kernel ensures that the parameters used by usb_alloc_coherent & usb_free_coherent calls in cdc-wdm.c match. Signed-off-by: Robert Lukassen Signed-off-by: Greg Kroah-Hartman Signed-off-by: Bjørn Mork --- diff --git a/drivers/usb/class/cdc-wdm.c b/drivers/usb/class/cdc-wdm.c index 949b448fd13e..696ca75fdea8 100644 --- a/drivers/usb/class/cdc-wdm.c +++ b/drivers/usb/class/cdc-wdm.c @@ -277,7 +277,7 @@ static void cleanup(struct wdm_device *desc) desc->sbuf, desc->validity->transfer_dma); usb_buffer_free(interface_to_usbdev(desc->intf), - desc->wMaxCommand, + desc->bMaxPacketSize0, desc->inbuf, desc->response->transfer_dma); kfree(desc->orq);