---

yaml
---
r: 215838
b: refs/heads/master
c: 512ba59
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: cbe487fac7fc016dbabbcbe83f11384e1803a56d
+refs/heads/master: 512ba59ed9c580b5e5575beda0041bb19a641127

trunk/arch/powerpc/kernel/kvm.c

@@ -42,6 +42,7 @@
 #define KVM_INST_B_MAX		0x01ffffff
 
 #define KVM_MASK_RT		0x03e00000
+#define KVM_RT_30		0x03c00000
 #define KVM_MASK_RB		0x0000f800
 #define KVM_INST_MFMSR		0x7c0000a6
 #define KVM_INST_MFSPR_SPRG0	0x7c1042a6
@@ -82,6 +83,15 @@ static inline void kvm_patch_ins(u32 *inst, u32 new_inst)
 	flush_icache_range((ulong)inst, (ulong)inst + 4);
 }
 
+static void kvm_patch_ins_ll(u32 *inst, long addr, u32 rt)
+{
+#ifdef CONFIG_64BIT
+	kvm_patch_ins(inst, KVM_INST_LD | rt | (addr & 0x0000fffc));
+#else
+	kvm_patch_ins(inst, KVM_INST_LWZ | rt | (addr & 0x0000fffc));
+#endif
+}
+
 static void kvm_patch_ins_ld(u32 *inst, long addr, u32 rt)
 {
 #ifdef CONFIG_64BIT
@@ -186,7 +196,6 @@ static void kvm_patch_ins_mtmsrd(u32 *inst, u32 rt)
 extern u32 kvm_emulate_mtmsr_branch_offs;
 extern u32 kvm_emulate_mtmsr_reg1_offs;
 extern u32 kvm_emulate_mtmsr_reg2_offs;
-extern u32 kvm_emulate_mtmsr_reg3_offs;
 extern u32 kvm_emulate_mtmsr_orig_ins_offs;
 extern u32 kvm_emulate_mtmsr_len;
 extern u32 kvm_emulate_mtmsr[];
@@ -216,9 +225,27 @@ static void kvm_patch_ins_mtmsr(u32 *inst, u32 rt)
 	/* Modify the chunk to fit the invocation */
 	memcpy(p, kvm_emulate_mtmsr, kvm_emulate_mtmsr_len * 4);
 	p[kvm_emulate_mtmsr_branch_offs] |= distance_end & KVM_INST_B_MASK;
-	p[kvm_emulate_mtmsr_reg1_offs] |= rt;
-	p[kvm_emulate_mtmsr_reg2_offs] |= rt;
-	p[kvm_emulate_mtmsr_reg3_offs] |= rt;
+
+	/* Make clobbered registers work too */
+	switch (get_rt(rt)) {
+	case 30:
+		kvm_patch_ins_ll(&p[kvm_emulate_mtmsr_reg1_offs],
+				 magic_var(scratch2), KVM_RT_30);
+		kvm_patch_ins_ll(&p[kvm_emulate_mtmsr_reg2_offs],
+				 magic_var(scratch2), KVM_RT_30);
+		break;
+	case 31:
+		kvm_patch_ins_ll(&p[kvm_emulate_mtmsr_reg1_offs],
+				 magic_var(scratch1), KVM_RT_30);
+		kvm_patch_ins_ll(&p[kvm_emulate_mtmsr_reg2_offs],
+				 magic_var(scratch1), KVM_RT_30);
+		break;
+	default:
+		p[kvm_emulate_mtmsr_reg1_offs] |= rt;
+		p[kvm_emulate_mtmsr_reg2_offs] |= rt;
+		break;
+	}
+
 	p[kvm_emulate_mtmsr_orig_ins_offs] = *inst;
 	flush_icache_range((ulong)p, (ulong)p + kvm_emulate_mtmsr_len * 4);
 
@@ -402,9 +429,7 @@ static void kvm_check_ins(u32 *inst, u32 features)
 		break;
 	case KVM_INST_MTMSR:
 	case KVM_INST_MTMSRD_L0:
-		/* We use r30 and r31 during the hook */
-		if (get_rt(inst_rt) < 30)
-			kvm_patch_ins_mtmsr(inst, inst_rt);
+		kvm_patch_ins_mtmsr(inst, inst_rt);
 		break;
 	}
 

trunk/arch/powerpc/kernel/kvm_emul.S

@@ -135,7 +135,8 @@ kvm_emulate_mtmsr:
 
 	/* Find the changed bits between old and new MSR */
 kvm_emulate_mtmsr_reg1:
-	xor	r31, r0, r31
+	ori	r30, r0, 0
+	xor	r31, r30, r31
 
 	/* Check if we need to really do mtmsr */
 	LOAD_REG_IMMEDIATE(r30, MSR_CRITICAL_BITS)
@@ -156,23 +157,25 @@ kvm_emulate_mtmsr_orig_ins:
 
 maybe_stay_in_guest:
 
+	/* Get the target register in r30 */
+kvm_emulate_mtmsr_reg2:
+	ori	r30, r0, 0
+
 	/* Check if we have to fetch an interrupt */
 	lwz	r31, (KVM_MAGIC_PAGE + KVM_MAGIC_INT)(0)
 	cmpwi	r31, 0
 	beq+	no_mtmsr
 
 	/* Check if we may trigger an interrupt */
-kvm_emulate_mtmsr_reg2:
-	andi.	r31, r0, MSR_EE
+	andi.	r31, r30, MSR_EE
 	beq	no_mtmsr
 
 	b	do_mtmsr
 
 no_mtmsr:
 
 	/* Put MSR into magic page because we don't call mtmsr */
-kvm_emulate_mtmsr_reg3:
-	STL64(r0, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0)
+	STL64(r30, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0)
 
 	SCRATCH_RESTORE
 
@@ -193,10 +196,6 @@ kvm_emulate_mtmsr_reg1_offs:
 kvm_emulate_mtmsr_reg2_offs:
 	.long (kvm_emulate_mtmsr_reg2 - kvm_emulate_mtmsr) / 4
 
-.global kvm_emulate_mtmsr_reg3_offs
-kvm_emulate_mtmsr_reg3_offs:
-	.long (kvm_emulate_mtmsr_reg3 - kvm_emulate_mtmsr) / 4
-
 .global kvm_emulate_mtmsr_orig_ins_offs
 kvm_emulate_mtmsr_orig_ins_offs:
 	.long (kvm_emulate_mtmsr_orig_ins - kvm_emulate_mtmsr) / 4