Re: gdb reload-uefi missing EFI_SYSTEM_TABLE_POINTER [was: Source code debugging of OVMF]

[Johannes Swoboda <johannes.swoboda@student.tuwien.ac.at>]

Hello,

I asked you for help for source level debugging of ovmf some time ago.
Things got in the way after that, but now I was able to follow your
advice and achieved my goal.

In particular,

1. I added the debug-lines below to GdbSyms.c
2. I started debugging later in the BDS phase (as suggested by several
of you)
3. I got rid of the qemu flag -enable-kvm (it screwed up the stepping in
gdb)

Thank you very much!

Kind regards,
Johannes


On 2018-04-24 04:13, Gary Lin wrote:
> On Fri, Apr 20, 2018 at 04:54:06PM +0200, Johannes Swoboda wrote:
>> gdb complained:
>>> Python Exception <class 'gdb.error'> No type named
>>> EFI_SYSTEM_TABLE_POINTER.:
>>> [...]
> I encountered the issue before and it seems caused by the linker option,
> "--whole-archive", which drops the symbols not used.
> 
> As a workaround, I add the following lines to Initialize():
> 
>   DEBUG ((DEBUG_VERBOSE, "%a: %llx\n", __FUNCTION__, &ESTP));
>   DEBUG ((DEBUG_VERBOSE, "%a: %llx\n", __FUNCTION__, &EDIITH));
>   DEBUG ((DEBUG_VERBOSE, "%a: %llx\n", __FUNCTION__, &EIDH));
>   DEBUG ((DEBUG_VERBOSE, "%a: %llx\n", __FUNCTION__, &EIOHU));
>   DEBUG ((DEBUG_VERBOSE, "%a: %llx\n", __FUNCTION__, &EIDDE));
>   DEBUG ((DEBUG_VERBOSE, "%a: %llx\n", __FUNCTION__, &EIDCNE));
>   DEBUG ((DEBUG_VERBOSE, "%a: %llx\n", __FUNCTION__, &EIDCRE));
>   DEBUG ((DEBUG_VERBOSE, "%a: %llx\n", __FUNCTION__, &EIDCME));
> 
> It at least makes the linker believe the symbols are important.
> Maybe you can try it.
> 
> Cheers,
> 
> Gary Lin