7 files changed, 78 insertions, 8 deletions

diff --git a/disas/arm-a64.cc b/disas/arm-a64.cc
index b0803f9cc3..b57256b267 100644
--- a/disas/arm-a64.cc
+++ b/disas/arm-a64.cc
@@ -42,7 +42,7 @@ public:
         stream_ = stream;
     }
 
-    void SetPrintf(int (*printf_fn)(FILE *, const char *, ...)) {
+    void SetPrintf(fprintf_function printf_fn) {
         printf_ = printf_fn;
     }
 
@@ -53,7 +53,7 @@ protected:
     }
 
 private:
-    int (*printf_)(FILE *, const char *, ...);
+    fprintf_function printf_;
     FILE *stream_;
 };
 
diff --git a/target-arm/kvm-stub.c b/target-arm/kvm-stub.c
index cd1849f72c..db2edc2c4c 100644
--- a/target-arm/kvm-stub.c
+++ b/target-arm/kvm-stub.c
@@ -17,7 +17,7 @@ bool write_kvmstate_to_list(ARMCPU *cpu)
     abort();
 }
 
-bool write_list_to_kvmstate(ARMCPU *cpu)
+bool write_list_to_kvmstate(ARMCPU *cpu, int level)
 {
     abort();
 }
diff --git a/target-arm/kvm.c b/target-arm/kvm.c
index 548bfd768d..b278542085 100644
--- a/target-arm/kvm.c
+++ b/target-arm/kvm.c
@@ -409,7 +409,7 @@ bool write_kvmstate_to_list(ARMCPU *cpu)
     return ok;
 }
 
-bool write_list_to_kvmstate(ARMCPU *cpu)
+bool write_list_to_kvmstate(ARMCPU *cpu, int level)
 {
     CPUState *cs = CPU(cpu);
     int i;
@@ -421,6 +421,10 @@ bool write_list_to_kvmstate(ARMCPU *cpu)
         uint32_t v32;
         int ret;
 
+        if (kvm_arm_cpreg_level(regidx) > level) {
+            continue;
+        }
+
         r.id = regidx;
         switch (regidx & KVM_REG_SIZE_MASK) {
         case KVM_REG_SIZE_U32:
diff --git a/target-arm/kvm32.c b/target-arm/kvm32.c
index d7e7d6877f..421ce0ea0d 100644
--- a/target-arm/kvm32.c
+++ b/target-arm/kvm32.c
@@ -153,6 +153,34 @@ bool kvm_arm_reg_syncs_via_cpreg_list(uint64_t regidx)
     }
 }
 
+typedef struct CPRegStateLevel {
+    uint64_t regidx;
+    int level;
+} CPRegStateLevel;
+
+/* All coprocessor registers not listed in the following table are assumed to
+ * be of the level KVM_PUT_RUNTIME_STATE. If a register should be written less
+ * often, you must add it to this table with a state of either
+ * KVM_PUT_RESET_STATE or KVM_PUT_FULL_STATE.
+ */
+static const CPRegStateLevel non_runtime_cpregs[] = {
+    { KVM_REG_ARM_TIMER_CNT, KVM_PUT_FULL_STATE },
+};
+
+int kvm_arm_cpreg_level(uint64_t regidx)
+{
+    int i;
+
+    for (i = 0; i < ARRAY_SIZE(non_runtime_cpregs); i++) {
+        const CPRegStateLevel *l = &non_runtime_cpregs[i];
+        if (l->regidx == regidx) {
+            return l->level;
+        }
+    }
+
+    return KVM_PUT_RUNTIME_STATE;
+}
+
 #define ARM_MPIDR_HWID_BITMASK 0xFFFFFF
 #define ARM_CPU_ID_MPIDR       0, 0, 0, 5
 
@@ -367,7 +395,7 @@ int kvm_arch_put_registers(CPUState *cs, int level)
      * managed to update the CPUARMState with, and only allowing those
      * to be written back up into the kernel).
      */
-    if (!write_list_to_kvmstate(cpu)) {
+    if (!write_list_to_kvmstate(cpu, level)) {
         return EINVAL;
     }
 
diff --git a/target-arm/kvm64.c b/target-arm/kvm64.c
index ac34f51498..bd60889d12 100644
--- a/target-arm/kvm64.c
+++ b/target-arm/kvm64.c
@@ -139,6 +139,34 @@ bool kvm_arm_reg_syncs_via_cpreg_list(uint64_t regidx)
     }
 }
 
+typedef struct CPRegStateLevel {
+    uint64_t regidx;
+    int level;
+} CPRegStateLevel;
+
+/* All system registers not listed in the following table are assumed to be
+ * of the level KVM_PUT_RUNTIME_STATE. If a register should be written less
+ * often, you must add it to this table with a state of either
+ * KVM_PUT_RESET_STATE or KVM_PUT_FULL_STATE.
+ */
+static const CPRegStateLevel non_runtime_cpregs[] = {
+    { KVM_REG_ARM_TIMER_CNT, KVM_PUT_FULL_STATE },
+};
+
+int kvm_arm_cpreg_level(uint64_t regidx)
+{
+    int i;
+
+    for (i = 0; i < ARRAY_SIZE(non_runtime_cpregs); i++) {
+        const CPRegStateLevel *l = &non_runtime_cpregs[i];
+        if (l->regidx == regidx) {
+            return l->level;
+        }
+    }
+
+    return KVM_PUT_RUNTIME_STATE;
+}
+
 #define AARCH64_CORE_REG(x)   (KVM_REG_ARM64 | KVM_REG_SIZE_U64 | \
                  KVM_REG_ARM_CORE | KVM_REG_ARM_CORE_REG(x))
 
@@ -280,7 +308,7 @@ int kvm_arch_put_registers(CPUState *cs, int level)
         return ret;
     }
 
-    if (!write_list_to_kvmstate(cpu)) {
+    if (!write_list_to_kvmstate(cpu, level)) {
         return EINVAL;
     }
 
diff --git a/target-arm/kvm_arm.h b/target-arm/kvm_arm.h
index 5abd5916d1..7912d7433d 100644
--- a/target-arm/kvm_arm.h
+++ b/target-arm/kvm_arm.h
@@ -69,8 +69,18 @@ int kvm_arm_init_cpreg_list(ARMCPU *cpu);
 bool kvm_arm_reg_syncs_via_cpreg_list(uint64_t regidx);
 
 /**
+ * kvm_arm_cpreg_level
+ * regidx: KVM register index
+ *
+ * Return the level of this coprocessor/system register.  Return value is
+ * either KVM_PUT_RUNTIME_STATE, KVM_PUT_RESET_STATE, or KVM_PUT_FULL_STATE.
+ */
+int kvm_arm_cpreg_level(uint64_t regidx);
+
+/**
  * write_list_to_kvmstate:
  * @cpu: ARMCPU
+ * @level: the state level to sync
  *
  * For each register listed in the ARMCPU cpreg_indexes list, write
  * its value from the cpreg_values list into the kernel (via ioctl).
@@ -83,7 +93,7 @@ bool kvm_arm_reg_syncs_via_cpreg_list(uint64_t regidx);
  * Note that we do not stop early on failure -- we will attempt
  * writing all registers in the list.
  */
-bool write_list_to_kvmstate(ARMCPU *cpu);
+bool write_list_to_kvmstate(ARMCPU *cpu, int level);
 
 /**
  * write_kvmstate_to_list:
diff --git a/target-arm/machine.c b/target-arm/machine.c
index 9eb51dfddd..32adfe792e 100644
--- a/target-arm/machine.c
+++ b/target-arm/machine.c
@@ -251,7 +251,7 @@ static int cpu_post_load(void *opaque, int version_id)
     }
 
     if (kvm_enabled()) {
-        if (!write_list_to_kvmstate(cpu)) {
+        if (!write_list_to_kvmstate(cpu, KVM_PUT_FULL_STATE)) {
             return -1;
         }
         /* Note that it's OK for the TCG side not to know about