[S390] kernel: always keep machine flags in lowcore

Eleminate the local variable machine_flags and always change machine
flags directly in the lowcore.
This avoids confusion about when and why the two variables have to be
synchronized.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 11 insertions, 17 deletions

diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c
index 21f3799fe27c..734deeaa7361 100644
--- a/arch/s390/kernel/early.c
+++ b/arch/s390/kernel/early.c
@@ -35,8 +35,6 @@
 
 char kernel_nss_name[NSS_NAME_SIZE + 1];
 
-static unsigned long machine_flags;
-
 static void __init setup_boot_command_line(void);
 
 /*
@@ -206,12 +204,9 @@ static noinline __init void detect_machine_type(void)
 
         /* Running under KVM? If not we assume z/VM */
         if (!memcmp(vmms.vm[0].cpi, "\xd2\xe5\xd4", 3))
-                machine_flags |= MACHINE_FLAG_KVM;
+                S390_lowcore.machine_flags |= MACHINE_FLAG_KVM;
         else
-                machine_flags |= MACHINE_FLAG_VM;
-
-        /* Store machine flags for setting up lowcore early */
-        S390_lowcore.machine_flags = machine_flags;
+                S390_lowcore.machine_flags |= MACHINE_FLAG_VM;
 }
 
 static __init void early_pgm_check_handler(void)
@@ -246,7 +241,7 @@ static noinline __init void setup_hpage(void)
         facilities = stfl();
         if (!(facilities & (1UL << 23)) || !(facilities & (1UL << 29)))
                 return;
-        machine_flags |= MACHINE_FLAG_HPAGE;
+        S390_lowcore.machine_flags |= MACHINE_FLAG_HPAGE;
         __ctl_set_bit(0, 23);
 #endif
 }
@@ -264,7 +259,7 @@ static __init void detect_mvpg(void)
                 EX_TABLE(0b,1b)
                 : "=d" (rc) : "0" (-EOPNOTSUPP), "a" (0) : "memory", "cc", "0");
         if (!rc)
-                machine_flags |= MACHINE_FLAG_MVPG;
+                S390_lowcore.machine_flags |= MACHINE_FLAG_MVPG;
 #endif
 }
 
@@ -280,7 +275,7 @@ static __init void detect_ieee(void)
                 EX_TABLE(0b,1b)
                 : "=d" (rc), "=d" (tmp): "0" (-EOPNOTSUPP) : "cc");
         if (!rc)
-                machine_flags |= MACHINE_FLAG_IEEE;
+                S390_lowcore.machine_flags |= MACHINE_FLAG_IEEE;
 #endif
 }
 
@@ -299,7 +294,7 @@ static __init void detect_csp(void)
                 EX_TABLE(0b,1b)
                 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc", "0", "1", "2");
         if (!rc)
-                machine_flags |= MACHINE_FLAG_CSP;
+                S390_lowcore.machine_flags |= MACHINE_FLAG_CSP;
 #endif
 }
 
@@ -316,7 +311,7 @@ static __init void detect_diag9c(void)
                 EX_TABLE(0b,1b)
                 : "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc");
         if (!rc)
-                machine_flags |= MACHINE_FLAG_DIAG9C;
+                S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG9C;
 }
 
 static __init void detect_diag44(void)
@@ -331,7 +326,7 @@ static __init void detect_diag44(void)
                 EX_TABLE(0b,1b)
                 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc");
         if (!rc)
-                machine_flags |= MACHINE_FLAG_DIAG44;
+                S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG44;
 #endif
 }
 
@@ -342,11 +337,11 @@ static __init void detect_machine_facilities(void)
 
         facilities = stfl();
         if (facilities & (1 << 28))
-                machine_flags |= MACHINE_FLAG_IDTE;
+                S390_lowcore.machine_flags |= MACHINE_FLAG_IDTE;
         if (facilities & (1 << 23))
-                machine_flags |= MACHINE_FLAG_PFMF;
+                S390_lowcore.machine_flags |= MACHINE_FLAG_PFMF;
         if (facilities & (1 << 4))
-                machine_flags |= MACHINE_FLAG_MVCOS;
+                S390_lowcore.machine_flags |= MACHINE_FLAG_MVCOS;
 #endif
 }
 
@@ -428,7 +423,6 @@ void __init startup_init(void)
         setup_hpage();
         sclp_facilities_detect();
         detect_memory_layout(memory_chunk);
-        S390_lowcore.machine_flags = machine_flags;
 #ifdef CONFIG_DYNAMIC_FTRACE
         S390_lowcore.ftrace_func = (unsigned long)ftrace_caller;
 #endif