[haiku-gsoc] Re: [ARM port] Fixing KDL memory access fault when printing the backtrace
- From: "Ithamar R. Adema" <ithamar@xxxxxxxxxxxxxxxxxxx>
- To: haiku-gsoc@xxxxxxxxxxxxx
- Date: Tue, 12 Aug 2014 10:40:39 -0400
Hey,
On Tue, Aug 12, 2014 at 10:31 AM, Arvind S Raj <sraj.arvind@xxxxxxxxx>
wrote:
> Hello Ithamar,
>
> On 12 August 2014 19:47, Ithamar R. Adema <ithamar@xxxxxxxxxxxxxxxxxxx>
> wrote:
> > I suspect our exception handling is broken to start with, it was never
> > tested for anything else then ARMv5. If that is the case, then the fault
> > handler handling will be broken too. I suspect that's what you are
> seeing.
>
> Ah I see. Should I investigate exception handlers or simply use the
> difference check and try to move things ahead? This is the last week
> of GSoC work so what would be the best thing to do :)?
>
Well, I suspect you will have to do something there to get any further
anyway. Currently lots of kernel ARM support code is simply hardcoded to
our previous ARMv5 target, and that code is now being run on a ARMv7 cpu,
with a completely different SoC.
I mean specifically the Interrupt Controller here, but I guess also timers
are SoC specific, at least on the ARMv5 it still was ;)
>
> > Way to go to get the kdebug> prompt though, tried any KDL hangman yet?
> ;)
>
> Well I don't know what KDL hangman is :) - did someone implement
> hangman in KDL(can't be but just getting the obvious possibility out
> of the way)?
LOL, our own dear mmu_man (François Revol) did exactly that :P
> Also, I'm not sure if I can since there seem to be no
> commands registered in KDL('Unknown command "help". Enter "help" to
> get a list of all supported commands.'). I suspect it's probably
> because KDL was arrived via panic and thus no commands are registered.
> I didn't investigate it much after that since I was investigating the
> double spinlock acquire which caused the KDL.
>
Well, I guess your that early that none of the subsystems have registered
their commands yet, not even the "standard" ones (which are registered
relatively "late", in this context at least).
Ithamar.
Other related posts: