How to get better debugging for the kernel.

[Pedro Giffuni]

On 13/08/2016 18:49, Gordon Ross wrote:
> Actually, mdb primaryliy uses Compact ANSI-C Type Format (CTF),
> which is in sections added to binaries by tools that convert from
> either dwarf or stabs.
>
> I've assumed FreeBSD already has CTF since dtrace normally uses it too...

Ah yes, FreeBSD gets CTF from dwarf. Indeed we had a student that worked 
for two GSoC projects on CTF-related projects.

I am not sure if the MDB port has advanced but you are looking for this 
page:
https://wiki.freebsd.org/PortingMDB

Enjoy,

Pedro.


>
> On Sat, Aug 13, 2016 at 1:22 PM, Pedro Giffuni <pfg at freebsd.org> wrote:
>> Gordon Ross wrote:
>>> I heard a rumor someone might be working on a port of illumos "mdb".
>>> Anyone know if that's true, and how far along it went?
>>>
>> FWIW, I heard the same rumor.
>>
>>> We depend heavily upon this tool for production support;
>>> so much that I'm not sure how we'd live without it.
>>
>> There is interest, and I have seen some attempt at work on it however
>> it is not something likely to bear much fruit because mdb knows nothing
>> about dwarf; AFAICT it knows only about stabs, which we don't use
>> at all.
>>
>> Also, Oracle did make some Dtrace enhancements in upstream gdb that
>> would be good to port.
>>
>> Pedro.