Re: [PATCH] x86/ptrace: Remove questionable TS_COMPAT usage in ptrace

From: Jan Kratochvil
Date: Mon Jun 20 2016 - 07:14:15 EST


On Mon, 20 Jun 2016 12:07:56 +0200, Pedro Alves wrote:
> On 06/18/2016 06:02 PM, Andy Lutomirski wrote:
> > Yuck. I should have dug in to the history. Why not just
> > unconditionally sign-extend eax when set by a 32-bit tracer?
>
> No idea.

Roland McGrath knows why he wrote it that way, Cced.

What if eax contains an address in 2GB..4GB range? I guess currently the
orig_eax check tries to verify %eax cannot contain an address.


Jan