X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;ds=sidebyside;f=kernel%2Farch%2Fpowerpc%2Fkvm%2Fbook3s_hv_rm_mmu.c;h=c6d601cc97640a85c06441499ef933f516c205e1;hb=ec0a2ed6d8a5e555edef907895c041e285fdb495;hp=b027a89737b62cee4399e63eb9d61232f156687d;hpb=342fa5dfa053559f47caad657132522496dcf1b3;p=kvmfornfv.git

diff --git a/kernel/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/kernel/arch/powerpc/kvm/book3s_hv_rm_mmu.c
index b027a8973..c6d601cc9 100644
--- a/kernel/arch/powerpc/kvm/book3s_hv_rm_mmu.c
+++ b/kernel/arch/powerpc/kvm/book3s_hv_rm_mmu.c
@@ -421,14 +421,20 @@ long kvmppc_do_h_remove(struct kvm *kvm, unsigned long flags,
 	rev = real_vmalloc_addr(&kvm->arch.revmap[pte_index]);
 	v = pte & ~HPTE_V_HVLOCK;
 	if (v & HPTE_V_VALID) {
-		u64 pte1;
-
-		pte1 = be64_to_cpu(hpte[1]);
 		hpte[0] &= ~cpu_to_be64(HPTE_V_VALID);
-		rb = compute_tlbie_rb(v, pte1, pte_index);
+		rb = compute_tlbie_rb(v, be64_to_cpu(hpte[1]), pte_index);
 		do_tlbies(kvm, &rb, 1, global_invalidates(kvm, flags), true);
-		/* Read PTE low word after tlbie to get final R/C values */
-		remove_revmap_chain(kvm, pte_index, rev, v, pte1);
+		/*
+		 * The reference (R) and change (C) bits in a HPT
+		 * entry can be set by hardware at any time up until
+		 * the HPTE is invalidated and the TLB invalidation
+		 * sequence has completed.  This means that when
+		 * removing a HPTE, we need to re-read the HPTE after
+		 * the invalidation sequence has completed in order to
+		 * obtain reliable values of R and C.
+		 */
+		remove_revmap_chain(kvm, pte_index, rev, v,
+				    be64_to_cpu(hpte[1]));
 	}
 	r = rev->guest_rpte & ~HPTE_GR_RESERVED;
 	note_hpte_modification(kvm, rev);