Re: [Qemu-devel] Re: Debugging a 64-bit kernel in qemu

[Markus Duft]

On 01/03/2011 01:15 PM, Markus Duft wrote:
> On 01/03/2011 12:15 PM, Jan Kiszka wrote:
> [snip]
[snip]
> actually, i find that Ted Harkington was right: in 0.11.1 i can debug 32 bit 
> code with qemu-system-x86_64 well enough (which means i debugged all the 32 
> bit part of my kernel without ever seen _any_ problem/non-working 
> feature/whatever). wouldn't it be better to have 64 bit debugging working in 
> the 64 bit version, with 32 bit mode working mostly (with whatever small 
> issues), rather than just completely dooming 64 bit debugging...?
> 

owh - spoke too soon. there must be more to it: i tried reverting 
5f30fa18ad043a841fe9f0c3917ac60f2519ebd1, which restores ability to debug my 64 
bit kernel just fine, but now i get the packet too long when trying to debug 32 
bit code....

wouldn't it be possible to implement some kind of explicit switch with qemu in 
the meantime, so i can choose what bitness i want to debug? I know, it's a 
problem with gdb under the hood, but still - it's really uncool debugging 
doesn't work in either of the two cases.

Regards, Markus

> any further ideas?
> 
> BTW, i did look around a little for this problem before (although i wasn't 
> aware of the thread you pointed me to). All those threads don't propose any 
> solution other than "fix gdb", which may or may not take ages.
> 
> Regards, Markus
> 
>>
>> Jan
>>
> 
>