Re: [Qemu-devel] Re: [PATCH 4/4] gdbstub: x86: Switch 64/32 bit registers dynamically

[Jan Kiszka]

Paul Brook wrote:
>>> You've just deliberately broken the qemu gdbstub. After your patch it is
>>> impossible to debug mixed 32/64-bit code.
>> Please give it a try as it's the other way around: You can't properly
>> debug mixed target code without my patch. 
> 
> Sure you can, you just need a gdb that doesn't suck.  As soon as you 
> encounter 
> actual mixed code (rather than just running the wrong qemu) your patch causes 
> things to die horribly.

Just to recall the situation (again, please actually try it): if you
have to debug code that switches between 16/32 bit and 64 bit, you
_can't_ debug the 16 or 32 bit part as gdb will stumble and fall over
qemu sending 64-bit register layout for 16/32 bit code. That is a gdb
limitation, but this patch is about dealing with it until it's resolved
in gdb.

Jan

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