Re: [Qemu-devel] [PATCH v1 18/22] target-arm: A64: Generalize update_spsel for the various ELs

[Edgar E. Iglesias]

On Tue, May 13, 2014 at 10:32:09AM -0700, Richard Henderson wrote:
> On 05/05/2014 11:08 PM, Edgar E. Iglesias wrote:
> > -    /* EL0 has no access rights to update SPSel, and this code
> > -     * assumes we are updating SP for EL1 while running as EL1.
> > -     */
> > -    assert(arm_current_pl(env) == 1);
> > +    /* EL0 has no access rights to update SPSel.  */
> > +    assert(cur_el >= 1 && cur_el <= 3);
> 
> The old comment makes it clear that we're not supposed to get here when 
> running
> as EL0.  The new comment makes this look like a possible DoS attack.

I've changed it to the following for next version:
    /* We rely on illegal updates to SPsel from EL0 to get trapped
     * at translation time.
     */

If you have better suggestions I'm happy to update.

Thanks,
Edgar