kvm: selftests: aarch64: pass vgic_irq guest args as a pointer

The guest in vgic_irq gets its arguments in a struct. This struct used
to fit nicely in a single register so vcpu_args_set() was able to pass
it by value by setting x0 with it. Unfortunately, this args struct grew
after some commits and some guest args became random (specically
kvm_supports_irqfd).

Fix this by passing the guest args as a pointer (after allocating some
guest memory for it).
Signed-off-by: Ricardo Koller <ricarkol@google.com>
Reported-by: Reiji Watanabe <reijiw@google.com>
Cc: Andrew Jones <drjones@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220127030858.3269036-3-ricarkol@google.com

tools/testing/selftests/kvm/aarch64/vgic_irq.c

@@ -472,10 +472,10 @@ static void test_restore_active(struct test_args *args, struct kvm_inject_desc *
 		guest_restore_active(args, MIN_SPI, 4, f->cmd);
 }
 
-static void guest_code(struct test_args args)
+static void guest_code(struct test_args *args)
 {
-	uint32_t i, nr_irqs = args.nr_irqs;
-	bool level_sensitive = args.level_sensitive;
+	uint32_t i, nr_irqs = args->nr_irqs;
+	bool level_sensitive = args->level_sensitive;
 	struct kvm_inject_desc *f, *inject_fns;
 
 	gic_init(GIC_V3, 1, dist, redist);
@@ -484,11 +484,11 @@ static void guest_code(struct test_args args)
 		gic_irq_enable(i);
 
 	for (i = MIN_SPI; i < nr_irqs; i++)
-		gic_irq_set_config(i, !args.level_sensitive);
+		gic_irq_set_config(i, !level_sensitive);
 
-	gic_set_eoi_split(args.eoi_split);
+	gic_set_eoi_split(args->eoi_split);
 
-	reset_priorities(&args);
+	reset_priorities(args);
 	gic_set_priority_mask(CPU_PRIO_MASK);
 
 	inject_fns  = level_sensitive ? inject_level_fns
@@ -497,17 +497,17 @@ static void guest_code(struct test_args args)
 	local_irq_enable();
 
 	/* Start the tests. */
-	for_each_supported_inject_fn(&args, inject_fns, f) {
-		test_injection(&args, f);
-		test_preemption(&args, f);
-		test_injection_failure(&args, f);
+	for_each_supported_inject_fn(args, inject_fns, f) {
+		test_injection(args, f);
+		test_preemption(args, f);
+		test_injection_failure(args, f);
 	}
 
 	/* Restore the active state of IRQs. This would happen when live
 	 * migrating IRQs in the middle of being handled.
 	 */
-	for_each_supported_activate_fn(&args, set_active_fns, f)
-		test_restore_active(&args, f);
+	for_each_supported_activate_fn(args, set_active_fns, f)
+		test_restore_active(args, f);
 
 	GUEST_DONE();
 }
@@ -739,6 +739,7 @@ static void test_vgic(uint32_t nr_irqs, bool level_sensitive, bool eoi_split)
 	int gic_fd;
 	struct kvm_vm *vm;
 	struct kvm_inject_args inject_args;
+	vm_vaddr_t args_gva;
 
 	struct test_args args = {
 		.nr_irqs = nr_irqs,
@@ -757,7 +758,9 @@ static void test_vgic(uint32_t nr_irqs, bool level_sensitive, bool eoi_split)
 	vcpu_init_descriptor_tables(vm, VCPU_ID);
 
 	/* Setup the guest args page (so it gets the args). */
-	vcpu_args_set(vm, 0, 1, args);
+	args_gva = vm_vaddr_alloc_page(vm);
+	memcpy(addr_gva2hva(vm, args_gva), &args, sizeof(args));
+	vcpu_args_set(vm, 0, 1, args_gva);
 
 	gic_fd = vgic_v3_setup(vm, 1, nr_irqs,
 			GICD_BASE_GPA, GICR_BASE_GPA);