Re: ptrace single-stepping change breaks Wine

Davide Libenzi
2004-11-21T21:33:01Z

On Fri, Nov 19, 2004 at 01:53:38PM -0800, Linus Torvalds wrote:
>
> On Fri, 19 Nov 2004, Daniel Jacobowitz wrote:
> >
> > I'm getting the feeling that the question of whether to step into
> > signal handlers is orthogonal to single-stepping; maybe it should be a
> > separate ptrace operation.
>
> I really don't see why. If a controlling process is asking for
> single-stepping, then it damn well should get it. It it doesn't want to
> single-step through a signal handler, then it could decide to just put a
> breakpoint on the return point (possibly by modifying the signal handler
> save area).

I'd agree with Linus here. A signal handler is part of the application, so
it should be single stepped in the same way other application code does.
My original patch simply reenabled the flag before returning to userspace,
and this had the consequence to single step into signal handlers too.

PS: I still cannot find the beginning this thread on lkml.

- Davide