On 01/08, Pedro Alves wrote: > > On 12/04/2012 05:59 PM, Oleg Nesterov wrote: > > > But If we want to allow to trace vsyscall's, hw bp doesn't look very > > nice imo. HBP_NUM = 4 and you need to setup 3 bp's to trace them all. > > Irrespective of the whole syscall tracing issue, allowing HW bkpts in > the vsyscall just seems like a bug fix to me.
And I never argued. I sent the patch iirc ;) > > That is why I think PTRACE_SYSCALL should "simply work" somehow. And > > so far I think that "just report syscall_exit with orig_ax = -1" is > > the best (and simple) solution. > > If you report exit alone, you'll confuse current GDB into mistaking > it for an enter, Sure. That is why I asked Jan. > > OK. We can do more. We can report both syscall_enter/exit and we can > > change orig_ax/ax temporary to "fool" the tracer, so that everything > > will look as a "normal" syscall. Like vsyscall_seccomp() does. > > > > But this needs much more changes. > > I'd just like to add, that if any new syscall related option is > to be added, can we please just go all the way and add > PTRACE_EVENT_SYSCALL_ENTER|PTRACE_EVENT_SYSCALL_EXIT instead? Oh yes, this was suggested many times. Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
