usbmon: don't call mon_dmapeek if DMA isn't being used
This patch (as755b) fixes a bug in usbmon. Rather than assuming all
USB host controllers use DMA, the code will check the usb_bus data
structure. If DMA isn't used, we don't want to try peeking into a
non-existent DMA buffer!
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/mon/usb_mon.h b/drivers/usb/mon/usb_mon.h
index 50efc8e..ab9d02d 100644
--- a/drivers/usb/mon/usb_mon.h
+++ b/drivers/usb/mon/usb_mon.h
@@ -20,6 +20,7 @@
struct dentry *dent_s; /* Debugging file */
struct dentry *dent_t; /* Text interface file */
struct usb_bus *u_bus;
+ int uses_dma;
/* Ref */
int nreaders; /* Under mon_lock AND mbus->lock */