On 11/15/23 3:06 PM, Bakul Shah wrote:
On Nov 15, 2023, at 7:57 AM, John Baldwin <j...@freebsd.org> wrote:
On 10/9/23 5:21 PM, Bakul Shah wrote:
Any hints on how to use bhyve's -G <port> option to debug a VM
kernel? I can connect to it from gdb with "target remote :<port>"
& bhyve stops the VM initially but beyond that I am not sure.
Ideally this should work just like an in-circuit-emulator, not
requiring anything special in the VM or kernel itself.
step only works on Intel CPUs currently (and is a bit fragile
anyway due to interrupts firing while you try to step, but that
happens for me in QEMU as well). Breakpoints should work fine.
I tend to use 'until' to do stepping (basically stepping via
temporary breakpoints) when debugging the kernel this way.
Thanks for your response!
I can ^C to stop the VM, examine the stack, set breakpoints,
continue etc. but when the breakpoint is hit, kgdb doesn't
regain control -- instead I get the usual
db> ...
prompt on the console. I guess I have to set some sysctl for
this?
Hmm, no, it shouldn't be breaking into DDB in the guest as the
breakpoint exception should be intercepted by the stub and
never made visible to the guest.
--
John Baldwin
