Apple

<key>Kernel</key>

<string>mach_kernel</string>

would it work if I replace the mach_kernel with full path name of the debug kernel like the

following

<key>Kernel</key>
<string>/Volumes/KernelDebugKit/DEBUG_Kernel/mach_kernel</string>

Also is there some kinda symbol server for the release versions of OSX kernel(s) ?


Thanks,
Pro

On Mar 30, 2015, at 4:45 PM, Prokash Sinha <email@hidden> wrote:

It’s all vas, having snapshots at nearest past is the quickest way to get back what I want.

Finally I got debugger connection going on using 10.9, and no explicit nvram boot-args changes. the plist file does it. The most important part you gave me is 0x40 that takes care of the ARP related hand-shake, w/o that I never had a connection success.

Thanks much Phil!

Pro
On Mar 30, 2015, at 6:55 AM, Phil Jordan <email@hidden> wrote:

You can always boot into the recovery partition or an OSX installer disc and edit the com.apple.Boot.plist from the command line.

phil

On Sat, Mar 28, 2015 at 5:03 PM, Prokash Sinha <email@hidden> wrote:

Thanks Phil,

The mistake I made was to take a snapshot before even trying to configure for kernel debugging. So I can not get into a situation where I can connect to the target using kdp protocol. And rightly so, I should have at least pinged the target even before trying to configure.

I will try the suggested steps you gave here.

I was hoping there should be a VHD (virtual harddisk ) that I could traverse ( hack ) to disable the configuration I made to plist.

Prokash

On 3/28/2015 6:48 AM, Phil Jordan wrote:

com.apple.Boot.plist will not modify nvram, but you can specify boot args via NVRAM. Depending on your setup, that might be more convenient.

The only way of resuming from the kernel debugger I'm aware of is to 'continue' from lldb.

Can you ping the VM when not stuck in the debugger? If not, this might be a routing issue - you might not be able to directly access the VM from the host if you're in "NAT" mode or similar.
The other thing is you're using debug=0x01 - I suggest trying with the DB_ARP (0x40) bit set as well. This enables ARP (address resolution protocol) even when stopped in the kernel debugger, which might help if the VM environment is adding a hop for whatever reason. (this shouldn't make a difference if you're bridging to the the VM though)

Also helpful, especially during early boot, are the 0x2 and 0x08 bits for outputting printf and kprintf. The latter requires a serial port or firewire - adding a serial port to your VM that writes to a file should be easy to do.

phil

--

http://philjordan.eu/ - Phil Jordan, software development contractor

--
http://philjordan.eu/ - Phil Jordan, software development contractor

References:
	>Setting up GDB (From: Prokash Sinha <email@hidden>)
	>Re: Setting up GDB (From: Shantonu Sen <email@hidden>)
	>Re: Setting up GDB (From: Prokash Sinha <email@hidden>)
	>Re: Setting up GDB (From: Gary Kratkin <email@hidden>)
	>Re: Setting up GDB (From: Prokash Sinha <email@hidden>)
	>Re: Setting up GDB (From: Phil Jordan <email@hidden>)
	>Re: Setting up GDB (From: Prokash Sinha <email@hidden>)
	>Re: Setting up GDB (From: Phil Jordan <email@hidden>)
	>Re: Setting up GDB (From: Prokash Sinha <email@hidden>)