KVM: remove kvm_arch_cpu_check_are_resettable

Board reset requires writing a fresh CPU state.  As far as KVM is
concerned, the only thing that blocks reset is that CPU state is
encrypted; therefore, kvm_cpus_are_resettable() can simply check
if that is the case.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

accel/kvm/kvm-accel-ops.c

@@ -82,7 +82,7 @@ static bool kvm_vcpu_thread_is_idle(CPUState *cpu)
 
 static bool kvm_cpus_are_resettable(void)
 {
-    return !kvm_enabled() || kvm_cpu_check_are_resettable();
+    return !kvm_enabled() || !kvm_state->guest_state_protected;
 }
 
 #ifdef TARGET_KVM_HAVE_GUEST_DEBUG

accel/kvm/kvm-all.c

@@ -2696,11 +2696,6 @@ void kvm_flush_coalesced_mmio_buffer(void)
     s->coalesced_flush_in_progress = false;
 }
 
-bool kvm_cpu_check_are_resettable(void)
-{
-    return kvm_arch_cpu_check_are_resettable();
-}
-
 static void do_kvm_cpu_synchronize_state(CPUState *cpu, run_on_cpu_data arg)
 {
     if (!cpu->vcpu_dirty && !kvm_state->guest_state_protected) {

include/sysemu/kvm.h

@@ -525,16 +525,6 @@ int kvm_get_one_reg(CPUState *cs, uint64_t id, void *target);
 /* Notify resamplefd for EOI of specific interrupts. */
 void kvm_resample_fd_notify(int gsi);
 
-/**
- * kvm_cpu_check_are_resettable - return whether CPUs can be reset
- *
- * Returns: true: CPUs are resettable
- *          false: CPUs are not resettable
- */
-bool kvm_cpu_check_are_resettable(void);
-
-bool kvm_arch_cpu_check_are_resettable(void);
-
 bool kvm_dirty_ring_enabled(void);
 
 uint32_t kvm_dirty_ring_size(void);

target/arm/kvm.c

@@ -1598,11 +1598,6 @@ int kvm_arch_msi_data_to_gsi(uint32_t data)
     return (data - 32) & 0xffff;
 }
 
-bool kvm_arch_cpu_check_are_resettable(void)
-{
-    return true;
-}
-
 static void kvm_arch_get_eager_split_size(Object *obj, Visitor *v,
                                           const char *name, void *opaque,
                                           Error **errp)

target/i386/kvm/kvm.c

@@ -5619,11 +5619,6 @@ bool kvm_has_waitpkg(void)
     return has_msr_umwait;
 }
 
-bool kvm_arch_cpu_check_are_resettable(void)
-{
-    return !sev_es_enabled();
-}
-
 #define ARCH_REQ_XCOMP_GUEST_PERM       0x1025
 
 void kvm_request_xsave_components(X86CPU *cpu, uint64_t mask)

target/loongarch/kvm/kvm.c

@@ -733,11 +733,6 @@ bool kvm_arch_stop_on_emulation_error(CPUState *cs)
     return true;
 }
 
-bool kvm_arch_cpu_check_are_resettable(void)
-{
-    return true;
-}
-
 int kvm_arch_handle_exit(CPUState *cs, struct kvm_run *run)
 {
     int ret = 0;

target/mips/kvm.c

@@ -1273,11 +1273,6 @@ int kvm_arch_get_default_type(MachineState *machine)
     return -1;
 }
 
-bool kvm_arch_cpu_check_are_resettable(void)
-{
-    return true;
-}
-
 void kvm_arch_accel_class_init(ObjectClass *oc)
 {
 }

target/ppc/kvm.c

@@ -2956,11 +2956,6 @@ void kvmppc_set_reg_tb_offset(PowerPCCPU *cpu, int64_t tb_offset)
     }
 }
 
-bool kvm_arch_cpu_check_are_resettable(void)
-{
-    return true;
-}
-
 void kvm_arch_accel_class_init(ObjectClass *oc)
 {
 }

target/riscv/kvm/kvm-cpu.c

@@ -1475,11 +1475,6 @@ void kvm_riscv_set_irq(RISCVCPU *cpu, int irq, int level)
     }
 }
 
-bool kvm_arch_cpu_check_are_resettable(void)
-{
-    return true;
-}
-
 static int aia_mode;
 
 static const char *kvm_aia_mode_str(uint64_t mode)

target/s390x/kvm/kvm.c

@@ -2622,11 +2622,6 @@ void kvm_s390_stop_interrupt(S390CPU *cpu)
     kvm_s390_vcpu_interrupt(cpu, &irq);
 }
 
-bool kvm_arch_cpu_check_are_resettable(void)
-{
-    return true;
-}
-
 int kvm_s390_get_zpci_op(void)
 {
     return cap_zpci_op;