Re: 64bit startup

[Luca]

Hi,

Il 09/06/23 19:49, Sergey Bugaev ha scritto:
> with the following hacky patch, I no longer see any crashes,
> debootstrap --second-stage runs all the way and leaves me with an
> almost full Debian GNU/Hurd x86_64 system \o/

I was able to avoid the issues with a different approach, basically 
commenting any write to ES/DS in x86_64/locore.S. In my case the 
corruption usually happens when handling the error of writing a bad 
value to ES/DS, and disabling this probably hides the corruption issue, 
but it's still a different issue that could be solved by just removing 
the useless segment handling.

It might be that the corruption itself is caused by a second trap/irq 
happening when the exit code from a first trap is executing (e.g. pop 
the last registers before iretq). This would enter the trap/irq handler 
using the same pcb stack, and probably some fsbase/gsbase push/pop is 
not done correctly in this case.


Luca