Re: [PATCH 2/3] x86: Pass in pt_regs pointer for syscalls that need it

["H. Peter Anvin" <hpa@zytor.com>]

Brian Gerst wrote:
> 
> I guess I could go back to extracting the args from the pt_regs struct
> given just the pointer.  How do you intend to handle system calls in
> your changes (normal ones, not needing pt_regs)?
> 

My plan was to by default load up the three first arguments in (%eax, 
%edx, %ecx) followed by the remaining arguments on the stack... I 
currently have it as a reorganized struct pt_regs, but I'm still trying 
to figure out if it would make more sense from a correctness and 
performance perspective to instead have duplicates of these entries.

For the pt_regs-using registers, they would need a tiny trampoline, 
looking like:

	leal 16(%esp),%eax
	jmp <real function>

	-hpa