Re: [stable] Why does timerfd() only support CLOCK_REALTIME and CLOCK_MONOTONIC?

[Greg KH <greg@kroah.com>]

On Sun, Feb 08, 2009 at 02:06:34PM -0800, Davide Libenzi wrote:
> On Mon, 9 Feb 2009, Michael Kerrisk wrote:
> 
> > On Mon, Feb 9, 2009 at 10:50 AM, Davide Libenzi <davidel@xmailserver.org> wrote:
> > > On Mon, 9 Feb 2009, Michael Kerrisk wrote:
> > >
> > >> > @@ -186,12 +187,9 @@ SYSCALL_DEFINE2(timerfd_create, int, clo
> > >> >        BUILD_BUG_ON(TFD_CLOEXEC != O_CLOEXEC);
> > >> >        BUILD_BUG_ON(TFD_NONBLOCK != O_NONBLOCK);
> > >> >
> > >> > -       if (flags & ~(TFD_CLOEXEC | TFD_NONBLOCK))
> > >> > +       if ((flags & ~TFD_FLAGS_SET) ||
> > >> > +           invalid_clockid(clockid))
> > >> >                return -EINVAL;
> > >>
> > >> Oh!  Does this mean that in 2.6.2[789] it wasn't possible to use
> > >> TFD_TIMER_ABSTIME?
> > >
> > > No, sorry, my fault. Patch is wrong. In "create" ATM we accept only
> > > FCNTL-like flags. In "settime" we get TFD_TIMER_ABSTIME (that needs a
> > > check too for EINVAL).
> > 
> > That last piece should be a separate patch, that also gets pushed back
> > into -stable.  Do you agree?
> 
> Hmm, it's a check for extra bits that do not cause any harm. Dunno if it 
> fits -stable requirements. You should ask Greg.

If it fixes a bug, it would go into -stable.  Does this?

thanks,

greg k-h