Re: [PATCH v2 3/10] KVM: MMU: fix direct sp's access corruptted

[Avi Kivity]

On 06/29/2010 12:04 PM, Xiao Guangrong wrote:
> > Simply replace (*spte&  SPTE_NO_DIRTY) with a condition that checks
> > whether sp->access is consistent with gw->pt(e)_access.
> >
> >      
> If the guest mapping is writable and it !dirty, we mark SPTE_NO_DIRTY flag in
> the spte, when the next #PF occurs, we just need check this flag and see whether
> gpte's D bit is set, if it's true, we zap this spte and map to the correct sp.
>    

My point is, SPTE_NO_DIRTY is equivalent to an sp->role.access check 
(the access check is a bit slower, but that shouldn't matter).


> > Can you write a test case for qemu-kvm.git/kvm/test that demonstrates
> > the problem and the fix?  It will help ensure we don't regress in this
> > area.
> >
> >      
> OK, but allow me do it later :-)
>
>    

Sure, but please do it soon.

--
error compiling committee.c: too many arguments to function

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/