On 1/10/22 1:14 PM, Warner Losh wrote:
On Mon, Jan 10, 2022 at 12:48 PM John Baldwin <[email protected]> wrote:
On 1/7/22 8:27 AM, Warner Losh wrote:
The branch main has been updated by imp:
URL:
https://cgit.FreeBSD.org/src/commit/?id=d6c0538dae8d138219dfd051994a44c50e741212
commit d6c0538dae8d138219dfd051994a44c50e741212
Author: Warner Losh <[email protected]>
AuthorDate: 2022-01-07 16:25:33 +0000
Commit: Warner Losh <[email protected]>
CommitDate: 2022-01-07 16:25:33 +0000
ddb: Remove SOFTWARE_SSTEP support
It was needed for mips only, and only kinda sorta worked for mips.
It
can be brought back if we grow another architecture that need it.
Sponsored by: Netflix
RISC-V would need it in theory (no hardware single step), but no one has
felt the
need to implement the backend support for it. I think 32-bit arm doesn't
support
hardware single step either (but again, no one has bothered to add the
backend
support).
Generally, I agree with these thoughts. I went ahead with the removal
because I
knew it would be easy to bring back, even years from now should someone[tm]
have an implementation for those platforms (though I thought 32-bit arm did
have
single step in hardware).
Should I put it back? Or should we wait until someone shows up with support
for
a supported platform?
I think the latter. I don't know that I've ever used single step in DDB on
any platform myself. In my experience, using a gdb stub in QEMU or via JTAG
or the like is a much better experience for debugging boot-time initialization.
--
John Baldwin
