1 files changed, 38 insertions, 32 deletions

diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c
index 6312fed48530..cd241ee66eff 100644
--- a/arch/s390/kernel/early.c
+++ b/arch/s390/kernel/early.c
@@ -30,8 +30,24 @@
 #include <asm/sclp.h>
 #include <asm/facility.h>
 #include <asm/boot_data.h>
+#include <asm/switch_to.h>
 #include "entry.h"
 
+static void __init reset_tod_clock(void)
+{
+	u64 time;
+
+	if (store_tod_clock(&time) == 0)
+		return;
+	/* TOD clock not running. Set the clock to Unix Epoch. */
+	if (set_tod_clock(TOD_UNIX_EPOCH) != 0 || store_tod_clock(&time) != 0)
+		disabled_wait();
+
+	memset(tod_clock_base, 0, 16);
+	*(__u64 *) &tod_clock_base[1] = TOD_UNIX_EPOCH;
+	S390_lowcore.last_update_clock = TOD_UNIX_EPOCH;
+}
+
 /*
  * Initialize storage key for kernel pages
  */
@@ -188,21 +204,6 @@ static __init void detect_diag9c(void)
 		S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG9C;
 }
 
-static __init void detect_diag44(void)
-{
-	int rc;
-
-	diag_stat_inc(DIAG_STAT_X044);
-	asm volatile(
-		"	diag	0,0,0x44\n"
-		"0:	la	%0,0\n"
-		"1:\n"
-		EX_TABLE(0b,1b)
-		: "=d" (rc) : "0" (-EOPNOTSUPP) : "cc");
-	if (!rc)
-		S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG44;
-}
-
 static __init void detect_machine_facilities(void)
 {
 	if (test_facility(8)) {
@@ -223,7 +224,7 @@ static __init void detect_machine_facilities(void)
 		S390_lowcore.machine_flags |= MACHINE_FLAG_VX;
 		__ctl_set_bit(0, 17);
 	}
-	if (test_facility(130)) {
+	if (test_facility(130) && !noexec_disabled) {
 		S390_lowcore.machine_flags |= MACHINE_FLAG_NX;
 		__ctl_set_bit(0, 20);
 	}
@@ -245,6 +246,24 @@ static inline void save_vector_registers(void)
 #endif
 }
 
+static inline void setup_control_registers(void)
+{
+	unsigned long reg;
+
+	__ctl_store(reg, 0, 0);
+	reg |= CR0_LOW_ADDRESS_PROTECTION;
+	reg |= CR0_EMERGENCY_SIGNAL_SUBMASK;
+	reg |= CR0_EXTERNAL_CALL_SUBMASK;
+	__ctl_load(reg, 0, 0);
+}
+
+static inline void setup_access_registers(void)
+{
+	unsigned int acrs[NUM_ACRS] = { 0 };
+
+	restore_access_regs(acrs);
+}
+
 static int __init disable_vector_extension(char *str)
 {
 	S390_lowcore.machine_flags &= ~MACHINE_FLAG_VX;
@@ -253,21 +272,6 @@ static int __init disable_vector_extension(char *str)
 }
 early_param("novx", disable_vector_extension);
 
-static int __init noexec_setup(char *str)
-{
-	bool enabled;
-	int rc;
-
-	rc = kstrtobool(str, &enabled);
-	if (!rc && !enabled) {
-		/* Disable no-execute support */
-		S390_lowcore.machine_flags &= ~MACHINE_FLAG_NX;
-		__ctl_clear_bit(0, 20);
-	}
-	return rc;
-}
-early_param("noexec", noexec_setup);
-
 static int __init cad_setup(char *str)
 {
 	bool enabled;
@@ -301,6 +305,7 @@ static void __init check_image_bootable(void)
 
 void __init startup_init(void)
 {
+	reset_tod_clock();
 	check_image_bootable();
 	time_early_init();
 	init_kernel_storage_key();
@@ -311,10 +316,11 @@ void __init startup_init(void)
 	setup_arch_string();
 	setup_boot_command_line();
 	detect_diag9c();
-	detect_diag44();
 	detect_machine_facilities();
 	save_vector_registers();
 	setup_topology();
 	sclp_early_detect();
+	setup_control_registers();
+	setup_access_registers();
 	lockdep_on();
 }