[SeaBIOS] [Question] Debug Seabios by GDB with Qemu

[Liu, Jing2]

On 2/5/2018 7:10 PM, Liu, Jing2 wrote:
> Hi Kevin,
> 
> On 1/31/2018 10:46 AM, Kevin O'Connor wrote:
>> On Mon, Jan 29, 2018 at 02:18:45PM +0800, Liu, Jing2 wrote:
>>> Hello,
>>>
>>> I am using Seabios for qemu startup, and interested in the debugging 
>>> by GDB
>>> to see how the bios works.
>>>
>>> Currently, I do it as https://www.seabios.org/Debugging said but met 
>>> some
>>> problems so that couldn't move on. :(
>>> Could someone give some pointers on what I missed or have to do to 
>>> enable
>>> the gdb debugging?
>>>
>>> Note:
>>> Arch: x86_64 PC
>>> CONFIG_DEBUG_SERIAL is enabled.
>>> CONFIG_RELOCATE_INIT is disabled.
>>>
>>> 1.  After Qemu starts, I run "gdb out/rom32seg.o" in another session, 
>>> and do
>>> "target remote localhost:1234", it warns me that
>>> "Selected architecture i386 is not compatible with reported target
>>> architecture i386:x86_64". But I didn't find any 64bit rom.
>>
>> I'm not sure why you choose out/rom32seg.o - to debug the 32bit code,
>> you want to use out/rom.o.
> 
> Thank you for your answer!
> But after I connect to qemu in the gdb session, and execute "run" OR 
> "start" to start the rom.o, it both reports me a signal SIGKILL.
> 
> I don't know why?

BTW, qemu can run correctly with the same bios when don't debug with "-S 
-s".

Thanks!

Jing
> 
> -Jing
>>
>> -Kevin
>>