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Diffstat (limited to 'arch/s390/kernel/nospec-branch.c')
-rw-r--r--arch/s390/kernel/nospec-branch.c17
1 files changed, 9 insertions, 8 deletions
diff --git a/arch/s390/kernel/nospec-branch.c b/arch/s390/kernel/nospec-branch.c
index 29e511f5bf06..250e4dbf653c 100644
--- a/arch/s390/kernel/nospec-branch.c
+++ b/arch/s390/kernel/nospec-branch.c
@@ -17,11 +17,11 @@ static int __init nobp_setup_early(char *str)
* The user explicitely requested nobp=1, enable it and
* disable the expoline support.
*/
- __set_facility(82, S390_lowcore.alt_stfle_fac_list);
+ __set_facility(82, alt_stfle_fac_list);
if (IS_ENABLED(CONFIG_EXPOLINE))
nospec_disable = 1;
} else {
- __clear_facility(82, S390_lowcore.alt_stfle_fac_list);
+ __clear_facility(82, alt_stfle_fac_list);
}
return 0;
}
@@ -29,7 +29,7 @@ early_param("nobp", nobp_setup_early);
static int __init nospec_setup_early(char *str)
{
- __clear_facility(82, S390_lowcore.alt_stfle_fac_list);
+ __clear_facility(82, alt_stfle_fac_list);
return 0;
}
early_param("nospec", nospec_setup_early);
@@ -40,7 +40,7 @@ static int __init nospec_report(void)
pr_info("Spectre V2 mitigation: etokens\n");
if (__is_defined(CC_USING_EXPOLINE) && !nospec_disable)
pr_info("Spectre V2 mitigation: execute trampolines\n");
- if (__test_facility(82, S390_lowcore.alt_stfle_fac_list))
+ if (__test_facility(82, alt_stfle_fac_list))
pr_info("Spectre V2 mitigation: limited branch prediction\n");
return 0;
}
@@ -66,14 +66,14 @@ void __init nospec_auto_detect(void)
*/
if (__is_defined(CC_USING_EXPOLINE))
nospec_disable = 1;
- __clear_facility(82, S390_lowcore.alt_stfle_fac_list);
+ __clear_facility(82, alt_stfle_fac_list);
} 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, S390_lowcore.alt_stfle_fac_list);
+ __clear_facility(82, alt_stfle_fac_list);
}
/*
* If the kernel has not been compiled with expolines the
@@ -86,7 +86,7 @@ static int __init spectre_v2_setup_early(char *str)
{
if (str && !strncmp(str, "on", 2)) {
nospec_disable = 0;
- __clear_facility(82, S390_lowcore.alt_stfle_fac_list);
+ __clear_facility(82, alt_stfle_fac_list);
}
if (str && !strncmp(str, "off", 3))
nospec_disable = 1;
@@ -99,6 +99,7 @@ early_param("spectre_v2", spectre_v2_setup_early);
static void __init_or_module __nospec_revert(s32 *start, s32 *end)
{
enum { BRCL_EXPOLINE, BRASL_EXPOLINE } type;
+ static const u8 branch[] = { 0x47, 0x00, 0x07, 0x00 };
u8 *instr, *thunk, *br;
u8 insnbuf[6];
s32 *epo;
@@ -128,7 +129,7 @@ static void __init_or_module __nospec_revert(s32 *start, s32 *end)
if ((br[0] & 0xbf) != 0x07 || (br[1] & 0xf0) != 0xf0)
continue;
- memcpy(insnbuf + 2, (char[]) { 0x47, 0x00, 0x07, 0x00 }, 4);
+ memcpy(insnbuf + 2, branch, sizeof(branch));
switch (type) {
case BRCL_EXPOLINE:
insnbuf[0] = br[0];