Re: SYSCALL, ptrace and syscall restart breakages (Re: [RFC] weird crap with vdso on uml/i386)

Al Viro
2011-08-21T14:51:53Z

On Sun, Aug 21, 2011 at 09:37:18AM -0400, Andrew Lutomirski wrote:

> Gack. Is this a holdover from the 32-bit code that shares the
> argument save area with the parameters passed on the C stack? If so,
> we could just set up the argument save area honestly and pass the real
> parameters in registers like 64-bit C code expects.
>
> If the tracing and restart cases use iret to return to userspace, this
> should all just work. ptrace users shouldn't notice the overhead, and
> syscall restart is presumably slow enough anyway that it wouldn't
> matter. The userspace entry code would be as simple as:
>
> sysenter
> ret
>
> or
>
> sysexit
> ret

You are making no sense at all...