arm: kvm: implement CPU PM notifier
Upon CPU shutdown and consequent warm-reboot, the hypervisor CPU state
must be re-initialized. This patch implements a CPU PM notifier that
upon warm-boot calls a KVM hook to reinitialize properly the hypervisor
state so that the CPU can be safely resumed.
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index 2a700e0..b18165c 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -17,6 +17,7 @@
*/
#include <linux/cpu.h>
+#include <linux/cpu_pm.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/kvm_host.h>
@@ -853,6 +854,33 @@
.notifier_call = hyp_init_cpu_notify,
};
+#ifdef CONFIG_CPU_PM
+static int hyp_init_cpu_pm_notifier(struct notifier_block *self,
+ unsigned long cmd,
+ void *v)
+{
+ if (cmd == CPU_PM_EXIT) {
+ cpu_init_hyp_mode(NULL);
+ return NOTIFY_OK;
+ }
+
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block hyp_init_cpu_pm_nb = {
+ .notifier_call = hyp_init_cpu_pm_notifier,
+};
+
+static void __init hyp_cpu_pm_init(void)
+{
+ cpu_pm_register_notifier(&hyp_init_cpu_pm_nb);
+}
+#else
+static inline void hyp_cpu_pm_init(void)
+{
+}
+#endif
+
/**
* Inits Hyp-mode on all online CPUs
*/
@@ -1013,6 +1041,8 @@
goto out_err;
}
+ hyp_cpu_pm_init();
+
kvm_coproc_table_init();
return 0;
out_err: