RFC: HW watchpoints and single stepping for ARMv6/v7

[Zbigniew Bodek]

Hello,

Thank you all for testing. Went upstream:  r294740

Best regards
zbb

2015-10-31 17:21 GMT+01:00 Zbigniew Bodek <zbb at semihalf.com>:

> Hello again,
>
> I should have post some more information about testing this patch. Here it
> goes:
> ------------------------------------------------------------------
> One can enter kernel debugger by one of those:
>
> press: ~, ctrl + b
> or
> type: sysctl -w debug.kdb.enter=1
>
> You can then set a HW watchpoint on any memory location at <address>
> by invoking following command in KDB:
> db> hwatch <address>, <size>
>
> <size> parameter is optional, the default is 4.
>
> To display watchpoints:
> db> show watch
>
> To remove watchpoint:
> db> dhwatch <address>
>
> Press "c" to continue.
>
> ------------------------------------------------------------------
> While in KDB you can step through the kernel code using "s" BUT you
> need to apply a dependent patch: https://reviews.freebsd.org/D4036
> otherwise you will cause the kernel panic.
>
> Thanks again
> zbb
>
> 2015-10-30 17:25 GMT+01:00 Zbigniew Bodek <zbb at semihalf.com>:
> > Hello,
> >
> > We would like to add HW watchpoints and HW single step support to ARMv6
> kernel.
> > Please check this review: https://reviews.freebsd.org/D4037
> >
> > Since there are differences between debug architectures on ARM (v6,
> > v6.1, v7, v7.1) I would like to ask for some testing on your machines.
> > I was able to test this on Pandaboard and Arndale but please check
> > whether this works on your targets as well.
> >
> > Rise a red flag if you see any issues or in worst case scenario -
> > "undefined instruction" error.
> >
> > Best regards
> > zbb
>