4.16-stable review patch. If anyone has any objections, please let me know.
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From: Martin Schwidefsky schwidefsky@de.ibm.com
[ 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@de.ibm.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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 */