ARM: KVM: perform HYP initilization for hotplugged CPUs
Now that we have the necessary infrastructure to boot a hotplugged CPU
at any point in time, wire a CPU notifier that will perform the HYP
init for the incoming CPU.
Note that this depends on the platform code and/or firmware to boot the
incoming CPU with HYP mode enabled and return to the kernel by following
the normal boot path (HYP stub installed).
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@cs.columbia.edu>
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index fc47bd7..6ea2aed 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -16,6 +16,7 @@
* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
+#include <linux/cpu.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/kvm_host.h>
@@ -785,7 +786,7 @@
}
}
-static void cpu_init_hyp_mode(void *vector)
+static void cpu_init_hyp_mode(void *dummy)
{
unsigned long long boot_pgd_ptr;
unsigned long long pgd_ptr;
@@ -805,12 +806,28 @@
__cpu_init_hyp_mode(boot_pgd_ptr, pgd_ptr, hyp_stack_ptr, vector_ptr);
}
+static int hyp_init_cpu_notify(struct notifier_block *self,
+ unsigned long action, void *cpu)
+{
+ switch (action) {
+ case CPU_STARTING:
+ case CPU_STARTING_FROZEN:
+ cpu_init_hyp_mode(NULL);
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block hyp_init_cpu_nb = {
+ .notifier_call = hyp_init_cpu_notify,
+};
+
/**
* Inits Hyp-mode on all online CPUs
*/
static int init_hyp_mode(void)
{
- phys_addr_t init_phys_addr;
int cpu;
int err = 0;
@@ -843,19 +860,6 @@
}
/*
- * Execute the init code on each CPU.
- *
- * Note: The stack is not mapped yet, so don't do anything else than
- * initializing the hypervisor mode on each CPU using a local stack
- * space for temporary storage.
- */
- init_phys_addr = virt_to_phys(__kvm_hyp_init);
- for_each_online_cpu(cpu) {
- smp_call_function_single(cpu, cpu_init_hyp_mode,
- (void *)(long)init_phys_addr, 1);
- }
-
- /*
* Map the Hyp-code called directly from the host
*/
err = create_hyp_mappings(__kvm_hyp_code_start, __kvm_hyp_code_end);
@@ -900,6 +904,11 @@
}
/*
+ * Execute the init code on each CPU.
+ */
+ on_each_cpu(cpu_init_hyp_mode, NULL, 1);
+
+ /*
* Init HYP view of VGIC
*/
err = kvm_vgic_hyp_init();
@@ -917,6 +926,10 @@
if (err)
goto out_free_mappings;
+#ifndef CONFIG_HOTPLUG_CPU
+ free_boot_hyp_pgd();
+#endif
+
kvm_perf_init();
kvm_info("Hyp mode initialized successfully\n");
@@ -955,6 +968,12 @@
if (err)
goto out_err;
+ err = register_cpu_notifier(&hyp_init_cpu_nb);
+ if (err) {
+ kvm_err("Cannot register HYP init CPU notifier (%d)\n", err);
+ goto out_err;
+ }
+
kvm_coproc_table_init();
return 0;
out_err: