> > I believe you need to *store* last value given to userland.
>
> But that's trivially done: it doesn't even have to be thread-specific, so
> it can be just a global entry anywhere in the process data
> structures.
> This is just a random sanity check thing, after all. It doesn't have to be
> system-global or even per-cpu. The only really important thing is that
> "gettimeofday()" should return monotonically increasing data - and if it
> doesn't, the vsyscall would have to ask why (sometimes it's fine, if
> somebody did a settimeofday, but usually it's a sign of trouble).
I believe you need it system-global. If task A tells task B "its
10:30:00" and than task B does gettimeofday and gets "10:29:59", it
will be confused for sure.
Pavel
-- Casualities in World Trade Center: ~3k dead inside the building, cryptography in U.S.A. and free speech in Czech Republic. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/