s390: dump_stack: fill in arch description

Lets provide the basic machine information for dump_stack on
s390. This enables the "Hardware name:" line and results in
output like

[...]
Oops: 0004 ilc:2 [#1] SMP
Modules linked in:
CPU: 1 PID: 74 Comm: sh Not tainted 4.5.0+ #205
Hardware name: IBM              2964 NC9              704	(KVM)
[...]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/kernel/early.c

@@ -231,6 +231,26 @@ static noinline __init void detect_machine_type(void)
 		S390_lowcore.machine_flags |= MACHINE_FLAG_VM;
 }
 
+static noinline __init void setup_arch_string(void)
+{
+	struct sysinfo_1_1_1 *mach = (struct sysinfo_1_1_1 *)&sysinfo_page;
+
+	if (stsi(mach, 1, 1, 1))
+		return;
+	EBCASC(mach->manufacturer, sizeof(mach->manufacturer));
+	EBCASC(mach->type, sizeof(mach->type));
+	EBCASC(mach->model, sizeof(mach->model));
+	EBCASC(mach->model_capacity, sizeof(mach->model_capacity));
+	dump_stack_set_arch_desc("%-16.16s %-4.4s %-16.16s %-16.16s (%s)",
+				 mach->manufacturer,
+				 mach->type,
+				 mach->model,
+				 mach->model_capacity,
+				 MACHINE_IS_LPAR ? "LPAR" :
+				 MACHINE_IS_VM ? "z/VM" :
+				 MACHINE_IS_KVM ? "KVM" : "unknown");
+}
+
 static __init void setup_topology(void)
 {
 	int max_mnest;
@@ -452,6 +472,7 @@ void __init startup_init(void)
 	setup_lowcore_early();
 	setup_facility_list();
 	detect_machine_type();
+	setup_arch_string();
 	ipl_update_parameters();
 	setup_boot_command_line();
 	create_kernel_nss();