I need to do some kernel debugging on a Windows 7 target system. Unfortunately, the machine has no RS232 or 1394 ports. While the machine physically has USB 3.0 ports, there are no win7 USB 3.0 drivers installed. I am trying to figure out my options for debugging.
I do not have a USB 2.0 debug cable and am having trouble finding one for sale anywhere – all the links I can find say no longer for sale. I have a USB 3.0 debug cable, but of course it will not work. Some questions:
Assuming I could get USB 3.0 drivers successfully installed (not sure if they are available for this server board), is this likely to work for USB debugging – can I even do USB 3.0 debugging on Windows 7?
Failing that, does anyone know where I could purchase a USB 2.0 debug cable?
What other options do I have – am I going to have to get and install 1394 cards on host and target?
Assuming I could get USB 3.0 drivers successfully installed (not sure if they are available for this server board), is this likely to work for USB debugging – can I even do USB 3.0 debugging on Windows 7?
No. The kernel debugger does not use the normal operating system
drivers. If you think about it, it can’t. It has to be totally
isolated from normal kernel operation. So, it talks to the hardware
directly with it’s own mini-drivers. The Windows 7 kernel debugger
doesn’t know anything about xHCI controllers.
What other options do I have – am I going to have to get and install 1394 cards on host and target?
Others have disagreed, but for me 1394 has always been the least
troublesome and most reliable kernel debug transport, at least until the
Ethernet transport became available. If you have PCIe slots, I’d
recommend it.
Thanks very much for the responses. 1394 is not ideal for a number of reasons, one of which is the laptop that I currently have as the debugger host does not have an express card slot. Also, while at the moment I believe it is not an issue on the current system, installing a PCI card on other targets may become problematic. Which is why I was looking to see if I could scare up a USB 2.0 debug cable, or get other ideas. But if I am stuck with 1394, then I will figure it out.
As we’ve written repeatedly and extensively… you absolutely do not want to rely on USB 2 debugging. When it works at all it barely works… when it doesn’t work it’s frustrating and annoying.
Not sure what specifically you are trying to debug. Depending on what it is, LiveKD might give you some insight into whats going on.
The other option that comes to mind, also less than ideal, is WPP tracing and then looking at the logs. At least extract the log from a dump file if you are debugging a crash.
@Sherri said:
Also, while at the moment I believe it is not an issue on the current system, installing a PCI card on other targets may become problematic. Which is why I was looking to see if I could scare up a USB 2.0 debug cable, or get other ideas.
I have a PCIe Firewire card that i use on systems that don’t have PCI. Doesn’t solve this specific issue but at least gives some hope for 1394 for a little longer.