Merge git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm fixes from Marcelo Tosatti.

* git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86 emulator: use stack size attribute to mask rsp in stack ops
  KVM: MMU: Fix mmu_shrink() so that it can free mmu pages as intended
  ppc: e500_tlb memset clears nothing
  KVM: PPC: Add cache flush on page map
  KVM: PPC: Book3S HV: Fix incorrect branch in H_CEDE code
  KVM: x86: update KVM_SAVE_MSRS_BEGIN to correct value

3 files changed, 31 insertions, 14 deletions

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 97d9a99..a3b57a2 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -475,13 +475,26 @@ register_address(struct x86_emulate_ctxt *ctxt, unsigned long reg)
 	return address_mask(ctxt, reg);
 }
 
+static void masked_increment(ulong *reg, ulong mask, int inc)
+{
+	assign_masked(reg, *reg + inc, mask);
+}
+
 static inline void
 register_address_increment(struct x86_emulate_ctxt *ctxt, unsigned long *reg, int inc)
 {
+	ulong mask;
+
 	if (ctxt->ad_bytes == sizeof(unsigned long))
-		*reg += inc;
+		mask = ~0UL;
 	else
-		*reg = (*reg & ~ad_mask(ctxt)) | ((*reg + inc) & ad_mask(ctxt));
+		mask = ad_mask(ctxt);
+	masked_increment(reg, mask, inc);
+}
+
+static void rsp_increment(struct x86_emulate_ctxt *ctxt, int inc)
+{
+	masked_increment(&ctxt->regs[VCPU_REGS_RSP], stack_mask(ctxt), inc);
 }
 
 static inline void jmp_rel(struct x86_emulate_ctxt *ctxt, int rel)
@@ -1522,8 +1535,8 @@ static int push(struct x86_emulate_ctxt *ctxt, void *data, int bytes)
 {
 	struct segmented_address addr;
 
-	register_address_increment(ctxt, &ctxt->regs[VCPU_REGS_RSP], -bytes);
-	addr.ea = register_address(ctxt, ctxt->regs[VCPU_REGS_RSP]);
+	rsp_increment(ctxt, -bytes);
+	addr.ea = ctxt->regs[VCPU_REGS_RSP] & stack_mask(ctxt);
 	addr.seg = VCPU_SREG_SS;
 
 	return segmented_write(ctxt, addr, data, bytes);
@@ -1542,13 +1555,13 @@ static int emulate_pop(struct x86_emulate_ctxt *ctxt,
 	int rc;
 	struct segmented_address addr;
 
-	addr.ea = register_address(ctxt, ctxt->regs[VCPU_REGS_RSP]);
+	addr.ea = ctxt->regs[VCPU_REGS_RSP] & stack_mask(ctxt);
 	addr.seg = VCPU_SREG_SS;
 	rc = segmented_read(ctxt, addr, dest, len);
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
 
-	register_address_increment(ctxt, &ctxt->regs[VCPU_REGS_RSP], len);
+	rsp_increment(ctxt, len);
 	return rc;
 }
 
@@ -1688,8 +1701,7 @@ static int em_popa(struct x86_emulate_ctxt *ctxt)
 
 	while (reg >= VCPU_REGS_RAX) {
 		if (reg == VCPU_REGS_RSP) {
-			register_address_increment(ctxt, &ctxt->regs[VCPU_REGS_RSP],
-							ctxt->op_bytes);
+			rsp_increment(ctxt, ctxt->op_bytes);
 			--reg;
 		}
 
@@ -2825,7 +2837,7 @@ static int em_ret_near_imm(struct x86_emulate_ctxt *ctxt)
 	rc = emulate_pop(ctxt, &ctxt->dst.val, ctxt->op_bytes);
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
-	register_address_increment(ctxt, &ctxt->regs[VCPU_REGS_RSP], ctxt->src.val);
+	rsp_increment(ctxt, ctxt->src.val);
 	return X86EMUL_CONTINUE;
 }
 
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 01ca004..7fbd0d2 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -4113,16 +4113,21 @@ static int mmu_shrink(struct shrinker *shrink, struct shrink_control *sc)
 		LIST_HEAD(invalid_list);
 
 		/*
+		 * Never scan more than sc->nr_to_scan VM instances.
+		 * Will not hit this condition practically since we do not try
+		 * to shrink more than one VM and it is very unlikely to see
+		 * !n_used_mmu_pages so many times.
+		 */
+		if (!nr_to_scan--)
+			break;
+		/*
 		 * n_used_mmu_pages is accessed without holding kvm->mmu_lock
 		 * here. We may skip a VM instance errorneosly, but we do not
 		 * want to shrink a VM that only started to populate its MMU
 		 * anyway.
 		 */
-		if (kvm->arch.n_used_mmu_pages > 0) {
-			if (!nr_to_scan--)
-				break;
+		if (!kvm->arch.n_used_mmu_pages)
 			continue;
-		}
 
 		idx = srcu_read_lock(&kvm->srcu);
 		spin_lock(&kvm->mmu_lock);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 42bce48..dce75b76 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -806,7 +806,7 @@ EXPORT_SYMBOL_GPL(kvm_rdpmc);
  * kvm-specific. Those are put in the beginning of the list.
  */
 
-#define KVM_SAVE_MSRS_BEGIN	9
+#define KVM_SAVE_MSRS_BEGIN	10
 static u32 msrs_to_save[] = {
 	MSR_KVM_SYSTEM_TIME, MSR_KVM_WALL_CLOCK,
 	MSR_KVM_SYSTEM_TIME_NEW, MSR_KVM_WALL_CLOCK_NEW,