topic Gary, in Software Archive

OpenVMS System Code Debugging

Gary_N_ — Wed, 29 Jun 2016 20:31:05 GMT

You may have heard that the venerable OpenVMS Operating System is being ported to X64 at last.

We have booted to the point where we really need to get our system code debug capabilities up to speed. On prior architectures (VAX, Alpha, IA64) our early boot process was debugged using XDELTA, a primitive bit of software which handles machine control and communicates with a host system over a dedicated network and physical protocol. I have been evaluating whether to port XDELTA or to replace it with a more modern solution. It is written in a proprietary language which will take some time to port if we go that route, so I am seeking more modern alternatives.

Reviewing the "Intel System Debugger" reference guide, it appears that this would be an excellent option for us, but I have a few questions about it and how best to proceed with bringing up a "new" (1978) operating system.

First, how do I go about contributing a new "OS Awareness" capability for the System Debugger? We have extensive debug and compiler expertise on our team, so I am primarily looking for contact with someone in the know about adding OS specific symbol tables, etc. and if there is a formal process or documentation regarding developing such an extension?

In some prior architecture ports, we used a Linux system as our host and we can do the same here, but I would prefer to see VMS awareness become official. Several of the original developers of the VMS Debugger (myself included) are now working at VSI, so we can make this happen.

Second, assuming that it will take some time to complete the above task, our immediate need is to have the low-level machine control required of any system level debugger, exam/deposit registers & memory, stepping, etc. We can develop this ourselves, but I assume this could be provided by the Intel System Debugger also. Is it practical for us to access this functionality so that we can adapt an interface with our host-side debug tools? Recall that we typically use a physical layer network connection between debug client and host, but we can certainly develop whatever is needed as an interface (JTAG, USB, etc.). So is there an accessible subset of the System Debugger that we can adapt for this purpose, or can someone point me to an appropriate low-level product or example for X86-64 system code debugging, specifically machine control?

Regards, Gary.Newsted@vmssoftware.com (VSI)

p.s. maybe you could add "VMS" or "OpenVMS" to your list of Operating System tags?

Hi Gary,

Hubert_H_Intel — Fri, 01 Jul 2016 09:21:50 GMT

Hi Gary,

I'll work on your request.

Regards, Hubert.

Hi Gary,

Hubert_H_Intel — Mon, 04 Jul 2016 07:55:14 GMT

Hi Gary,

Our Intel® Platform Analysis Library (Intel® PAL) may be helpful. It's a software library containing debug, trace and monitoring APIs for Intel® architecture. Especially the Intel Debug Support Library might be a starting point; it's a set of APIs that facilitates software debugging on Intel® architecutre CPUs, allowing developers to quickly impolement a JTAG system debug solution.

Please check out the options on the webpage https://software.intel.com/de-de/intel-platform-analysis-technology

Regards, Hubert.

It is good that I speak a

Gary_N_ — Wed, 06 Jul 2016 16:04:50 GMT

It is good that I speak a bit of Deutsch... ;^)

Thank you Hubert, this has helped me very much. I am still however, interested in how we would go about adding an "OS Awareness" module to the Intel System Debugger? Is this documented? The product overview claims to have such modules for Windows and Linux. Presumably this is for symbol table support, but is it also possible to extend support for OS-specific languages too? This is just an inquiry at this point, so if this is not possible or practical that's all I need to know.

I have seen one possible alternative emerge for early kernel debug using features in the Platform Analysis Library combined with Eclipse plugins and our physical layer network protocol we use today. Now I need to judge whether this type of solution can come together faster than we can port our existing system code debugging tools (due to proprietary and, elderly, languages they were written in).

Best Regards, Gary

Hubert, I have yet to gain

Gary_N_ — Mon, 18 Jul 2016 14:48:58 GMT

Hubert, I have yet to gain access to the Platform Analysis Library that you pointed me to. It requires a Corporate Non-Disclosure Agreement, which we do have. I provided our CNDA number with my request but have not received any further correspondence. Is this something you can check info for me?

Regards, Gary at VSI

Gary, I'll check. Hubert.

Hubert_H_Intel — Thu, 21 Jul 2016 09:22:36 GMT

Gary,

I'll check.

Hubert.

Gary,

Hubert_H_Intel — Mon, 01 Aug 2016 11:52:21 GMT

Gary,

I heard that it would take a couple of days to complete the approval. But meanwhile you should have received a notifiaction. If this is not the case, let me know.

Regards, Hubert.

Gary,

Hubert_H_Intel — Fri, 05 Aug 2016 14:25:28 GMT

Gary,

Any progress yet?

Hubert.