KVM: PPC: Add check if pte was mapped secondary

Some HTAB providers (namely the PS3) ignore the SECONDARY flag. They
just put an entry in the htab as secondary when they see fit.

So we need to check the return value of htab_insert to remember the
correct slot id so we can actually invalidate the entry again.

Fixes KVM on the PS3.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/powerpc/kvm/book3s_64_mmu_host.c b/arch/powerpc/kvm/book3s_64_mmu_host.c
index 25bd4ed..a01e9c5 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_host.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_host.c
@@ -270,6 +270,13 @@
 			    (rflags & HPTE_R_N) ? '-' : 'x',
 			    orig_pte->eaddr, hpteg, va, orig_pte->vpage, hpaddr);
 
+		/* The ppc_md code may give us a secondary entry even though we
+		   asked for a primary. Fix up. */
+		if ((ret & _PTEIDX_SECONDARY) && !(vflags & HPTE_V_SECONDARY)) {
+			hash = ~hash;
+			hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP);
+		}
+
 		pte->slot = hpteg + (ret & 7);
 		pte->host_va = va;
 		pte->pte = *orig_pte;