4.16-stable review patch. If anyone has any objections, please let me know.
------------------
From: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
[ Upstream commit b2e2f43a01bace1a25bdbae04c9f9846882b727a ]
Keep the code for the nobp parameter handling with the code for
expolines. Both are related to the spectre v2 mitigation.
Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/s390/kernel/Makefile | 4 ++--
arch/s390/kernel/alternative.c | 23 -----------------------
arch/s390/kernel/nospec-branch.c | 27 +++++++++++++++++++++++++++
3 files changed, 29 insertions(+), 25 deletions(-)
--- a/arch/s390/kernel/Makefile
+++ b/arch/s390/kernel/Makefile
@@ -61,11 +61,11 @@ obj-y += debug.o irq.o ipl.o dis.o diag.
obj-y += sysinfo.o jump_label.o lgr.o os_info.o machine_kexec.o pgm_check.o
obj-y += runtime_instr.o cache.o fpu.o dumpstack.o guarded_storage.o sthyi.o
obj-y += entry.o reipl.o relocate_kernel.o kdebugfs.o alternative.o
+obj-y += nospec-branch.o
extra-y += head.o head64.o vmlinux.lds
-obj-$(CONFIG_EXPOLINE) += nospec-branch.o
-CFLAGS_REMOVE_expoline.o += $(CC_FLAGS_EXPOLINE)
+CFLAGS_REMOVE_nospec-branch.o += $(CC_FLAGS_EXPOLINE)
obj-$(CONFIG_MODULES) += module.o
obj-$(CONFIG_SMP) += smp.o
--- a/arch/s390/kernel/alternative.c
+++ b/arch/s390/kernel/alternative.c
@@ -15,29 +15,6 @@ static int __init disable_alternative_in
early_param("noaltinstr", disable_alternative_instructions);
-static int __init nobp_setup_early(char *str)
-{
- bool enabled;
- int rc;
-
- rc = kstrtobool(str, &enabled);
- if (rc)
- return rc;
- if (enabled && test_facility(82))
- __set_facility(82, S390_lowcore.alt_stfle_fac_list);
- else
- __clear_facility(82, S390_lowcore.alt_stfle_fac_list);
- return 0;
-}
-early_param("nobp", nobp_setup_early);
-
-static int __init nospec_setup_early(char *str)
-{
- __clear_facility(82, S390_lowcore.alt_stfle_fac_list);
- return 0;
-}
-early_param("nospec", nospec_setup_early);
-
struct brcl_insn {
u16 opc;
s32 disp;
--- a/arch/s390/kernel/nospec-branch.c
+++ b/arch/s390/kernel/nospec-branch.c
@@ -2,6 +2,31 @@
#include <linux/module.h>
#include <asm/nospec-branch.h>
+static int __init nobp_setup_early(char *str)
+{
+ bool enabled;
+ int rc;
+
+ rc = kstrtobool(str, &enabled);
+ if (rc)
+ return rc;
+ if (enabled && test_facility(82))
+ __set_facility(82, S390_lowcore.alt_stfle_fac_list);
+ else
+ __clear_facility(82, S390_lowcore.alt_stfle_fac_list);
+ return 0;
+}
+early_param("nobp", nobp_setup_early);
+
+static int __init nospec_setup_early(char *str)
+{
+ __clear_facility(82, S390_lowcore.alt_stfle_fac_list);
+ return 0;
+}
+early_param("nospec", nospec_setup_early);
+
+#ifdef CONFIG_EXPOLINE
+
int nospec_call_disable = IS_ENABLED(CONFIG_EXPOLINE_OFF);
int nospec_return_disable = !IS_ENABLED(CONFIG_EXPOLINE_FULL);
@@ -98,3 +123,5 @@ void __init nospec_init_branches(void)
nospec_call_revert(__nospec_call_start, __nospec_call_end);
nospec_return_revert(__nospec_return_start, __nospec_return_end);
}
+
+#endif /* CONFIG_EXPOLINE */
