How to list threads in WinDbg (kernel debugging)

Question

Does anyone know how I can list all threads in WinDbg while kernel debugging. I have found older references that say '~' but that does not work.

Specifically I am looking to the find the ID of a thread that caused an event, namely a breakpoint.

Thanks.

Solution 1

~ only works in user mode. To list all threads on the system, it's !process 0 1 as I recall (it's been awhile).

"Specifically I am looking to the find the ID of a thread that caused an event, namely a breakpoint."

This statement doesn't make much sense to do from kernel mode. Can you descrive more about what your scenario is?

Edit: Ah, now I get it. You want to know which thread you're currently in right now. Give !thread a go.

Solution 2

You can always use the @$thread pseudo register to reference the current thread object:

0: kd> r @$thread
$thread=fffff80002c02cc0

If you want the ID of the thread, you'll need to dig it out of the ETHREAD. Luckily, the @$thread is typed as a pointer to an ETHREAD if you're using the C++ evaluator:

0: kd> ?? @$thread->Cid
struct _CLIENT_ID
   +0x000 UniqueProcess    : 0x00000000`00001408 Void
   +0x008 UniqueThread     : 0x00000000`0000144c Void

-scott

Comments

[user963228]

Yeh, I have a breakpoint on NtLoadDriver, just would like to know the ID of the thread that raises the exception.

[cwhisperer]

How are you setting the breakpoint? You can't set or intercept breakpoints on user-mode code by default while in a kernel debugger.

[user963228]

I mean NtLoadDriver in ntoskrnl, so the thread is already executing in supervisor mode (ring 0). With debug symbols I just type kd> bp NtLoadDriver

[user963228]

and it breaks fine as expected when I expect it too. Im just looking for a way to retrieve the ID of the thread that is raising the exception.

[Isaac]

For the record, it should be !process 0 2 to show threads for each process. If you also want a stack trace, you can use !process 0 6. This gets extremely verbose though, so I'd recommend providing a specific process to look at instead of using 0.