Hi Paolo, Any comments? Thanks! B.R. Yu On Sat, Jan 16, 2021 at 08:21:00AM +0800, Yu Zhang wrote: > In shadow page table, only leaf SPs may be marked as unsync. > And for non-leaf SPs, we use unsync_children to keep the number > of the unsynced children. In kvm_mmu_sync_root(), sp->unsync > shall always be zero for the root SP, hence no need to check it. > > Signed-off-by: Yu Zhang <yu.c.zhang@xxxxxxxxxxxxxxx> > --- > arch/x86/kvm/mmu/mmu.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c > index 6d16481a..1a6bb03 100644 > --- a/arch/x86/kvm/mmu/mmu.c > +++ b/arch/x86/kvm/mmu/mmu.c > @@ -3412,8 +3412,7 @@ void kvm_mmu_sync_roots(struct kvm_vcpu *vcpu) > * mmu_need_write_protect() describe what could go wrong if this > * requirement isn't satisfied. > */ > - if (!smp_load_acquire(&sp->unsync) && > - !smp_load_acquire(&sp->unsync_children)) > + if (!smp_load_acquire(&sp->unsync_children)) > return; > > spin_lock(&vcpu->kvm->mmu_lock); > -- > 1.9.1 >
