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Hi...I am burned out from trying to establish a kernel debugging connection over serial. My host is a laptop running Win 7 x64 using a USB-serial adapter on COM2 @115200 baud. My target is a desktop running Win 7 x64 with an onboard serial connector on COM2 @115200 baud. The target is set in debug mode on COM2 @115200...verified by bcdedit.
I have verified that both computers are talking over the serial connection using several serial monitors. When I set Windbg in kernel mode, on [email protected] Baud, it indicates a connection to COM2 but it sits there with a notice, "waiting to connect". At this time, wdbg is frozen, no commands can be entered. If I try it with KD, I can still enter some commands.
While the KD debugger was running I entered .server then <ctrl-> enter and it spawned a debug the debugger window with cdb. By setting up a pipe using the same pipe as offered in KD, in the target in a KD window (started as KD -kl), I got communication between CDB and the target KD. The connection is very fast but the pipe is likely using the network cable. Don't know.
When I start windbg in kernel mode and it is 'waiting to reconnect', I am supposed to reboot the target machine. I verified that the target is loading kdcom.dll early in the debug boot but kdcom.dll does not show up in the list of running process once debug mode reaches the desktop. kdcom.dll is listed as the 3rd driver loaded, behind ntoskrnl and HAL.
Hitting ctrl-break many times in the wdbg host does nothing.
Someone mentioned that Windows connects directly with the serial ports but that is not possible. It must go through a driver to access the serial ports and I think that's what kdcom.dll is supposed to do. If it's not loaded, it won't be doing much.
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