On Wed, 2010-12-22 at 09:01 -0200, Marcelo Tosatti wrote: > If a pagetable contains a writeable large spte, all of its sptes will be > write protected, including non-leaf ones, leading to endless pagefaults. > > Do not write protect pages above PT_PAGE_TABLE_LEVEL, as the spte fault > paths assume non-leaf sptes are writable. > > Signed-off-by: Marcelo Tosatti <mtosatti@xxxxxxxxxx> > > diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c > index c3853d5..c716ff8 100644 > --- a/arch/x86/kvm/mmu.c > +++ b/arch/x86/kvm/mmu.c > @@ -3442,6 +3442,9 @@ void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot) > if (!test_bit(slot, sp->slot_bitmap)) > continue; > > + if (sp->role.level != PT_PAGE_TABLE_LEVEL) > + continue; > + > pt = sp->spt; > for (i = 0; i < PT64_ENT_PER_PAGE; ++i) > /* avoid RMW */ Works for me. Tested-by: Alex Williamson <alex.williamson@xxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
