RE: [PATCH] KVM: arm: Fix crash in free_hyp_pgds() if timer initialization fails

[Pavel Fedin <p.fedin@samsung.com>]

 Hello!

> >> The thing I want to avoid is PAGE_HYP_DEVICE covering some normal S2
> >> mapping, which we *should* flush but that we now end up ignoring?  That
> >> doesn't sound like it can be the case because the device bit is the same
> >> bit for both types of page tables, correct?
> >
> >  Yes, this is exactly what i think. If DEVICE bit is set, then it's somehow
> > device memory and it doesn't need flashing.
> >
> >  Or, in order to be 200% sure, we could modify the whole unmapping logic to carry
> > over a flag, telling whether we are removing normal or HYP mappings. But wouldn't
> > this be much more complicated?
> 
> We could do without that complexity. Also, the test itself is wrong (see
> Ard's patch that was posted this morning for the real fix).

 Good. Saw it, will test it on monday. Indeed, this is better than my approach, and
this is what i actually wanted to do but didn't study the thing deeply enough to
implement.

Kind regards,
Pavel Fedin
Expert Engineer
Samsung Electronics Research center Russia