diff options
Diffstat (limited to 'arch/s390/kernel/nospec-branch.c')
| -rw-r--r-- | arch/s390/kernel/nospec-branch.c | 20 |
1 files changed, 11 insertions, 9 deletions
diff --git a/arch/s390/kernel/nospec-branch.c b/arch/s390/kernel/nospec-branch.c index d1b16d83e49a..e11ec15960a1 100644 --- a/arch/s390/kernel/nospec-branch.c +++ b/arch/s390/kernel/nospec-branch.c @@ -4,6 +4,8 @@ #include <linux/cpu.h> #include <asm/nospec-branch.h> +int nobp = IS_ENABLED(CONFIG_KERNEL_NOBP); + static int __init nobp_setup_early(char *str) { bool enabled; @@ -17,11 +19,11 @@ static int __init nobp_setup_early(char *str) * The user explicitly requested nobp=1, enable it and * disable the expoline support. */ - __set_facility(82, alt_stfle_fac_list); + nobp = 1; if (IS_ENABLED(CONFIG_EXPOLINE)) nospec_disable = 1; } else { - __clear_facility(82, alt_stfle_fac_list); + nobp = 0; } return 0; } @@ -29,7 +31,7 @@ early_param("nobp", nobp_setup_early); static int __init nospec_setup_early(char *str) { - __clear_facility(82, alt_stfle_fac_list); + nobp = 0; return 0; } early_param("nospec", nospec_setup_early); @@ -40,7 +42,7 @@ static int __init nospec_report(void) pr_info("Spectre V2 mitigation: etokens\n"); if (nospec_uses_trampoline()) pr_info("Spectre V2 mitigation: execute trampolines\n"); - if (__test_facility(82, alt_stfle_fac_list)) + if (nobp_enabled()) pr_info("Spectre V2 mitigation: limited branch prediction\n"); return 0; } @@ -66,14 +68,14 @@ void __init nospec_auto_detect(void) */ if (__is_defined(CC_USING_EXPOLINE)) nospec_disable = 1; - __clear_facility(82, alt_stfle_fac_list); + nobp = 0; } else if (__is_defined(CC_USING_EXPOLINE)) { /* * The kernel has been compiled with expolines. * Keep expolines enabled and disable nobp. */ nospec_disable = 0; - __clear_facility(82, alt_stfle_fac_list); + nobp = 0; } /* * If the kernel has not been compiled with expolines the @@ -86,7 +88,7 @@ static int __init spectre_v2_setup_early(char *str) { if (str && !strncmp(str, "on", 2)) { nospec_disable = 0; - __clear_facility(82, alt_stfle_fac_list); + nobp = 0; } if (str && !strncmp(str, "off", 3)) nospec_disable = 1; @@ -114,10 +116,10 @@ static void __init_or_module __nospec_revert(s32 *start, s32 *end) type = BRASL_EXPOLINE; /* brasl instruction */ else continue; - thunk = instr + (*(int *)(instr + 2)) * 2; + thunk = instr + (long)(*(int *)(instr + 2)) * 2; if (thunk[0] == 0xc6 && thunk[1] == 0x00) /* exrl %r0,<target-br> */ - br = thunk + (*(int *)(thunk + 2)) * 2; + br = thunk + (long)(*(int *)(thunk + 2)) * 2; else continue; if (br[0] != 0x07 || (br[1] & 0xf0) != 0xf0) |