Headaches Getting Remote Debugging Working

WINDBG
1

I have been struggling to get remote debugging working with my target
machine. I first tried IEEE 1394, but after reading that some chipsets
have problems, I ordered the 1394 card from OSR and fell back to a null
modem cable. I can’t get that to work either.

I did do some searching, but the target machine’s setup might have
something to do with it. It’s a dual boot Win 7 and XP machine with
EasyBCD for the boot menu. I’ve found EasyBCD to be very touchy and
rather limited for the XP side. I’m trying to debug a driver on XP first.

It doesn’t look like it’s possible to set up multiple boot
configurations in boot.ini when dual booting with newer OSes. Maybe I’m
wrong there, but in any case I’ve put the debug information in the one
boot line in boot.ini so XP always boots to debug mode.

There is one com port built in that is connected to COM1. I’ve been
able to communicate across the null modem cable with Hyperterminal, but
no communication via windbg. All I get it the Waiting to connect…
message. The mother board has connectors for three other COM ports and
tried hooking up connectors to a couple of them. Oddly Windows comes up
with two Com ports enabled, but the second one varies between Com2 and
Com3. I put connectors on both and tried to communicate via
Hyperterminal with no luck.

The XP boot.ini parameters are:
/fastdetect /debug /debugport=COM1 /baudrate=38400

I tried this setup on another computer and the host saw it immediately
on boot, so the cable is good and the parameters worked on another
computer. The main difference with the other computer is that it only
has XP on it and I set a separate boot line for debugging which I select
from the boot menu when I want to go into that mode. I don’t think it
should cause a problem to only have one boot line with the debug info
there, but it’s getting to a point where I’m running out of
possibilities. Another possible problem is EasyBCD is doing something
that screws up enabling the boot parameters for debugging.

Am I going to have to kill the Win 7 boot on this computer to get
debugging happening? Why did Microsoft change the boot stuff anyway?

Bill

2

Do you by any chance have boot debugging enabled for the Win7 boot manager?

mm

3

No I don’t. I haven’t done anything debug related with Win 7.

Bill

On 11/12/10 3:09 AM, xxxxx@gmail.com wrote:

Do you by any chance have boot debugging enabled for the Win7 boot manager?

mm

WINDBG is sponsored by OSR

For our schedule of WDF, WDM, debugging and other seminars visit:
http://www.osr.com/seminars

To unsubscribe, visit the List Server section of OSR Online at http://www.osronline.com/page.cfm?name=ListServer

4

I can’t speak for EasyBCD having never used it (to be honest I would just use bcd.exe for this as it’s universally there and the commands for enabling debugging are easy enough to memorize). Here’s what I usually do for a machine I’ll be debugging over serial though (enables kernel debugging and boot manager debugging):

Bcdedit /set debug on
Bcdedit /set bootdebug on
Bcdedit /dbgsettings serial debugport:1 baudrate:115200

This assumes that COM1 on the machine is the port to use.

Boot debugging is optional in most cases, but it can be useful if you are developing a boot-start driver.

  • S

-----Original Message-----
From: xxxxx@lists.osr.com [mailto:xxxxx@lists.osr.com] On Behalf Of Bill Olson
Sent: Friday, November 12, 2010 4:26 AM
To: Kernel Debugging Interest List
Cc: xxxxx@gmail.com
Subject: Re: [windbg] Headaches Getting Remote Debugging Working

No I don’t. I haven’t done anything debug related with Win 7.

Bill

On 11/12/10 3:09 AM, xxxxx@gmail.com wrote:

Do you by any chance have boot debugging enabled for the Win7 boot manager?

mm

WINDBG is sponsored by OSR

For our schedule of WDF, WDM, debugging and other seminars visit:
http://www.osr.com/seminars

To unsubscribe, visit the List Server section of OSR Online at http://www.osronline.com/page.cfm?name=ListServer

WINDBG is sponsored by OSR

For our schedule of WDF, WDM, debugging and other seminars visit:
http://www.osr.com/seminars

To unsubscribe, visit the List Server section of OSR Online at http://www.osronline.com/page.cfm?name=ListServer

5

Is BCD.exe one of the new boot files with Vista and Win 7? If so, I
can’t find anything about it. I googled it and found some information
claiming it was a trojan, but nothing else useful.

The machine is dual boot with Win 7 and XP, but I’m debugging the XP
side. Bcdedit is only for Vista and Win 7 isn’t it? From my research
it’s not possible to dual boot a post XP OS with an XP or earlier OS
without a third party boot loader and it seems that EasyBCD is the most
common one out there. If there is a better way to set this system up to
dual boot, I’m all ears.

Bill

On 11/12/10 7:27 PM, Skywing wrote:

I can’t speak for EasyBCD having never used it (to be honest I would
just use bcd.exe for this as it’s universally there and the commands
for enabling debugging are easy enough to memorize). Here’s what I
usually do for a machine I’ll be debugging over serial though
(enables kernel debugging and boot manager debugging):

Bcdedit /set debug on Bcdedit /set bootdebug on Bcdedit /dbgsettings
serial debugport:1 baudrate:115200

This assumes that COM1 on the machine is the port to use.

Boot debugging is optional in most cases, but it can be useful if you
are developing a boot-start driver.

  • S

-----Original Message----- From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Bill Olson
Sent: Friday, November 12, 2010 4:26 AM To: Kernel Debugging Interest
List Cc: xxxxx@gmail.com Subject: Re: [windbg]
Headaches Getting Remote Debugging Working

No I don’t. I haven’t done anything debug related with Win 7.

Bill

On 11/12/10 3:09 AM, xxxxx@gmail.com wrote:
> Do you by any chance have boot debugging enabled for the Win7 boot
> manager?
>
>
> mm
>
> — WINDBG is sponsored by OSR
>
> For our schedule of WDF, WDM, debugging and other seminars visit:
> http://www.osr.com/seminars
>
> To unsubscribe, visit the List Server section of OSR Online at
> http://www.osronline.com/page.cfm?name=ListServer
>

— WINDBG is sponsored by OSR

For our schedule of WDF, WDM, debugging and other seminars visit:
http://www.osr.com/seminars

To unsubscribe, visit the List Server section of OSR Online at
http://www.osronline.com/page.cfm?name=ListServer

— WINDBG is sponsored by OSR

For our schedule of WDF, WDM, debugging and other seminars visit:
http://www.osr.com/seminars

To unsubscribe, visit the List Server section of OSR Online at
http://www.osronline.com/page.cfm?name=ListServer

6

Bcdedit.exe, not bcd.exe, sorry. You don’t need a third party boot loader to dual boot XP with Vista/win7, it will just call the legacy boot loader for that boot option IIRC.

  • S

-----Original Message-----
From: xxxxx@toc-cs.com [mailto:xxxxx@toc-cs.com] On Behalf Of Bill Olson
Sent: Friday, November 12, 2010 7:43 PM
To: Kernel Debugging Interest List
Cc: Skywing; xxxxx@gmail.com
Subject: Re: [windbg] Headaches Getting Remote Debugging Working

Is BCD.exe one of the new boot files with Vista and Win 7? If so, I can’t find anything about it. I googled it and found some information claiming it was a trojan, but nothing else useful.

The machine is dual boot with Win 7 and XP, but I’m debugging the XP side. Bcdedit is only for Vista and Win 7 isn’t it? From my research it’s not possible to dual boot a post XP OS with an XP or earlier OS without a third party boot loader and it seems that EasyBCD is the most common one out there. If there is a better way to set this system up to dual boot, I’m all ears.

Bill

On 11/12/10 7:27 PM, Skywing wrote:

I can’t speak for EasyBCD having never used it (to be honest I would
just use bcd.exe for this as it’s universally there and the commands
for enabling debugging are easy enough to memorize). Here’s what I
usually do for a machine I’ll be debugging over serial though
(enables kernel debugging and boot manager debugging):

Bcdedit /set debug on Bcdedit /set bootdebug on Bcdedit /dbgsettings
serial debugport:1 baudrate:115200

This assumes that COM1 on the machine is the port to use.

Boot debugging is optional in most cases, but it can be useful if you
are developing a boot-start driver.

  • S

-----Original Message----- From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Bill Olson
Sent: Friday, November 12, 2010 4:26 AM To: Kernel Debugging Interest
List Cc: xxxxx@gmail.com Subject: Re: [windbg]
Headaches Getting Remote Debugging Working

No I don’t. I haven’t done anything debug related with Win 7.

Bill

On 11/12/10 3:09 AM, xxxxx@gmail.com wrote:
> Do you by any chance have boot debugging enabled for the Win7 boot
> manager?
>
>
> mm
>
> — WINDBG is sponsored by OSR
>
> For our schedule of WDF, WDM, debugging and other seminars visit:
> http://www.osr.com/seminars
>
> To unsubscribe, visit the List Server section of OSR Online at
> http://www.osronline.com/page.cfm?name=ListServer
>

— WINDBG is sponsored by OSR

For our schedule of WDF, WDM, debugging and other seminars visit:
http://www.osr.com/seminars

To unsubscribe, visit the List Server section of OSR Online at
http://www.osronline.com/page.cfm?name=ListServer

— WINDBG is sponsored by OSR

For our schedule of WDF, WDM, debugging and other seminars visit:
http://www.osr.com/seminars

To unsubscribe, visit the List Server section of OSR Online at
http://www.osronline.com/page.cfm?name=ListServer

7

“Bill Olson” wrote in message news:xxxxx@windbg…
…
> I’m trying to debug a driver on XP first.
> It doesn’t look like it’s possible to set up multiple boot configurations
> in boot.ini when dual booting with newer OSes. Maybe I’m wrong there, but
> in any case I’ve put the debug information in the one boot line in
> boot.ini so XP always boots to debug mode.

A good solution. With only one choice in boot.ini no chance to mistake.
And boot.ini is easy to edit.

> There is one com port built in that is connected to COM1. I’ve been able
> to communicate across the null modem cable with Hyperterminal, but no
> communication via windbg. All I get it the Waiting to connect… message.
> The mother board has connectors for three other COM ports and tried
> hooking up connectors to a couple of them. Oddly Windows comes up with
> two Com ports enabled, but the second one varies between Com2 and Com3.

This is normal. After COM1 is taken by the debugger, other port numbers
shift.
Have you tried to disable other COM ports in the BIOS? If not, try.
(also, if the port is encumbered with alternate functions,
like remote console redirection, IR, RS485 and so on - disable them)

> Why did Microsoft change the boot stuff anyway?

This is the progress… no matter how good the old thing is, it ought to be
replaced.

–pa