Subject: Problem with MmProbeAndLockPages

NTDEV
1

What do you know, I turn my back to attend to some urgent debugging, and
this snippet kicks my behind ! I don't have the post any longer, but I was
told that it says,

===============
I noticed that the IRQL at which I call MmProbeAndLockPages, is
DISPATCH_LEVEL. Amazing. Must not be so. Can you show us the call stack
(WinDbg is better
for this then SoftICE, it can save the debugging session to a text file)?"

Well I beg to disagree ! The problem with SoftICE is that we cannot load
symbols when the system is stopped, because, well, the system's stopped. If
however the user preloads symbols for ntoskrnl, and any other important
items that may be on the stack our stack walking is 100% accurate.

Note that in the case of Windbg, all the intelligence is in the host system,
so, the target my be stopped and you can still load symbols on the fly
because it's done in the host side. However, if you need to load symbols on
the fly, you can use Visual SoftICE, it's part of DriverStudio !

Secondly, it is not true that we can save the SoftICE log. This is
inaccurate. If doing remote debugging you can always save it on the remote
machine. If you are not going to crash and at any other time, you can also
save it via Symbol Loader.

Alberto.

-----Original Message-----
From: Ellis, Bill
Sent: Wednesday, September 17, 2003 7:41 AM
To: Plakyda,Chris
Subject: RE: ntdev digest: September 16, 2003

Feel like correcting him? (history configuration)

-----Original Message-----
From: Andrei Ciubotaru [mailto:xxxxx@rdslink.ro]
Sent: Wednesday, September 17, 2003 6:07 AM
To: Windows System Software Devs Interest List
Subject: [ntdev] DVD structure

Hello,

Can anyone help me with the DVD geometry?

bytes per sector = ???
sectors per track = ???
tracks per cylinder = ???
cylinders = ???

Thank you,
Andrei Ciubotaru

Questions? First check the Kernel Driver FAQ at
http://www.osronline.com/article.cfm?id=256

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2

Still living in the ice age I wanted to write something similar but forgot
because had some urgent work. Well, I use SoftICE daily and don’t have
problems with incorrect stack. As Alberto pointed out, it is necessary to
prepare debugging session and preload all important symbols. Currently,
computers have a lot of memory so it isn’t a problem (I have 2 MB reserved
for symbols).

The same with log, simply use nmsym /log:log.txt. GUI also allows it some
way. Yes, it is a problem if OS just crashed. On SMP machine the situation
may not be so bad. If page fault occurs in kernel mode, SI traps it and
instead of BSOD the result is busy loop which blocks one CPU. Next CPUs are
free and it is possible to return to user mode and do anything necessary and
then shutdown. However, I’d recommend to improve it and allow log saving in
any situation. SI could preallocate a space on a disk and save log during
crash similarly as OS saves crashdump.

I don’t want to restart infinite Soft ICE versus WinDbg thread. Use whatever
debugger you like for whatever reasons. Just don’t post misinformations
about others.

Best regards,

Michal Vodicka
STMicroelectronics Design and Application s.r.o.
[michal.vodicka@st.com, http:://www.st.com]

From:
xxxxx@compuware.com[SMTP:xxxxx@compuware.com]
Reply To: xxxxx@lists.osr.com
Sent: Wednesday, September 17, 2003 5:06 PM
To: xxxxx@lists.osr.com
Subject: [ntdev] Subject: Problem with MmProbeAndLockPages

What do you know, I turn my back to attend to some urgent debugging, and
this snippet kicks my behind ! I don’t have the post any longer, but I was
told that it says,

===============
I noticed that the IRQL at which I call MmProbeAndLockPages, is
DISPATCH_LEVEL. Amazing. Must not be so. Can you show us the call stack
(WinDbg is better
for this then SoftICE, it can save the debugging session to a text file)?"

Well I beg to disagree ! The problem with SoftICE is that we cannot load
symbols when the system is stopped, because, well, the system’s stopped.
If
however the user preloads symbols for ntoskrnl, and any other important
items that may be on the stack our stack walking is 100% accurate.

Note that in the case of Windbg, all the intelligence is in the host
system,
so, the target my be stopped and you can still load symbols on the fly
because it’s done in the host side. However, if you need to load symbols
on
the fly, you can use Visual SoftICE, it’s part of DriverStudio !

Secondly, it is not true that we can save the SoftICE log. This is
inaccurate. If doing remote debugging you can always save it on the
remote
machine. If you are not going to crash and at any other time, you can
also
save it via Symbol Loader.

Alberto.