From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
Factor out the logic on cpu hotplug event as arch callback. Later kvm/x86
will override it.
Suggested-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
---
include/linux/kvm_host.h | 1 +
virt/kvm/kvm_main.c | 58 +++++++++++++++++++++++-----------------
2 files changed, 34 insertions(+), 25 deletions(-)
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 1adbf74e3047..013b33a19030 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1434,6 +1434,7 @@ void kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu, struct dentry *debugfs_
static inline void kvm_create_vcpu_debugfs(struct kvm_vcpu *vcpu) {}
#endif
+int kvm_arch_online_cpu(unsigned int cpu, int usage_count);
int kvm_arch_reboot(int val);
int kvm_arch_suspend(int usage_count);
void kvm_arch_resume(int usage_count);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 1270f88c2a1e..4c535ae412a7 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1142,6 +1142,38 @@ int __weak kvm_arch_del_vm(int usage_count)
return 0;
}
+int __weak kvm_arch_online_cpu(unsigned int cpu, int usage_count)
+{
+ int ret = 0;
+
+ ret = kvm_arch_check_processor_compat();
+ if (ret)
+ return ret;
+
+ /*
+ * Abort the CPU online process if hardware virtualization cannot
+ * be enabled. Otherwise running VMs would encounter unrecoverable
+ * errors when scheduled to this CPU.
+ */
+ if (usage_count) {
+ WARN_ON_ONCE(atomic_read(&hardware_enable_failed));
+
+ /*
+ * arch callback kvm_arch_hardware_eanble() assumes that
+ * preemption is disabled for historical reason. Disable
+ * preemption until all arch callbacks are fixed.
+ */
+ preempt_disable();
+ hardware_enable_nolock(NULL);
+ preempt_enable();
+ if (atomic_read(&hardware_enable_failed)) {
+ atomic_set(&hardware_enable_failed, 0);
+ ret = -EIO;
+ }
+ }
+ return ret;
+}
+
int __weak kvm_arch_reboot(int val)
{
on_each_cpu(hardware_disable_nolock, NULL, 1);
@@ -5085,32 +5117,8 @@ static int kvm_online_cpu(unsigned int cpu)
{
int ret;
- ret = kvm_arch_check_processor_compat();
- if (ret)
- return ret;
-
mutex_lock(&kvm_lock);
- /*
- * Abort the CPU online process if hardware virtualization cannot
- * be enabled. Otherwise running VMs would encounter unrecoverable
- * errors when scheduled to this CPU.
- */
- if (kvm_usage_count) {
- WARN_ON_ONCE(atomic_read(&hardware_enable_failed));
-
- /*
- * arch callback kvm_arch_hardware_eanble() assumes that
- * preemption is disabled for historical reason. Disable
- * preemption until all arch callbacks are fixed.
- */
- preempt_disable();
- hardware_enable_nolock(NULL);
- preempt_enable();
- if (atomic_read(&hardware_enable_failed)) {
- atomic_set(&hardware_enable_failed, 0);
- ret = -EIO;
- }
- }
+ ret = kvm_arch_online_cpu(cpu, kvm_usage_count);
mutex_unlock(&kvm_lock);
return ret;
}
--
2.25.1
