[S390] add MACHINE_IS_LPAR flag

Introduce the MACHINE_IS_LPAR flag for code that should only be
executed if Linux is running in an LPAR.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

3 files changed, 11 insertions, 5 deletions

diff --git a/arch/s390/include/asm/setup.h b/arch/s390/include/asm/setup.h
index 52a779c337e8..76f530b65f00 100644
--- a/arch/s390/include/asm/setup.h
+++ b/arch/s390/include/asm/setup.h
@@ -71,9 +71,12 @@ extern unsigned int user_mode;
 #define MACHINE_FLAG_KVM        (1UL << 9)
 #define MACHINE_FLAG_HPAGE      (1UL << 10)
 #define MACHINE_FLAG_PFMF       (1UL << 11)
+#define MACHINE_FLAG_LPAR       (1UL << 12)
 
 #define MACHINE_IS_VM           (S390_lowcore.machine_flags & MACHINE_FLAG_VM)
 #define MACHINE_IS_KVM          (S390_lowcore.machine_flags & MACHINE_FLAG_KVM)
+#define MACHINE_IS_LPAR         (S390_lowcore.machine_flags & MACHINE_FLAG_LPAR)
+
 #define MACHINE_HAS_DIAG9C      (S390_lowcore.machine_flags & MACHINE_FLAG_DIAG9C)
 
 #ifndef __s390x__
diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c
index e49e9e0c69fd..02e45861b55b 100644
--- a/arch/s390/kernel/early.c
+++ b/arch/s390/kernel/early.c
@@ -214,10 +214,13 @@ static __initdata struct sysinfo_3_2_2 vmms __aligned(PAGE_SIZE);
 
 static noinline __init void detect_machine_type(void)
 {
-        /* No VM information? Looks like LPAR */
-        if (stsi(&vmms, 3, 2, 2) == -ENOSYS)
+        /* Check current-configuration-level */
+        if ((stsi(NULL, 0, 0, 0) >> 28) <= 2) {
+                S390_lowcore.machine_flags |= MACHINE_FLAG_LPAR;
                 return;
-        if (!vmms.count)
+        }
+        /* Get virtual-machine cpu information. */
+        if (stsi(&vmms, 3, 2, 2) == -ENOSYS || !vmms.count)
                 return;
 
         /* Running under KVM? If not we assume z/VM */
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index 8d8957b38ab3..d9fb98cde0fa 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -804,7 +804,7 @@ setup_arch(char **cmdline_p)
         if (MACHINE_IS_VM)
                 pr_info("Linux is running as a z/VM "
                         "guest operating system in 31-bit mode\n");
-        else
+        else if (MACHINE_IS_LPAR)
                 pr_info("Linux is running natively in 31-bit mode\n");
         if (MACHINE_HAS_IEEE)
                 pr_info("The hardware system has IEEE compatible "
@@ -818,7 +818,7 @@ setup_arch(char **cmdline_p)
                         "guest operating system in 64-bit mode\n");
         else if (MACHINE_IS_KVM)
                 pr_info("Linux is running under KVM in 64-bit mode\n");
-        else
+        else if (MACHINE_IS_LPAR)
                 pr_info("Linux is running natively in 64-bit mode\n");
 #endif /* CONFIG_64BIT */