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Diffstat (limited to 'arch/arm64/kernel/idreg-override.c')
-rw-r--r--arch/arm64/kernel/idreg-override.c105
1 files changed, 90 insertions, 15 deletions
diff --git a/arch/arm64/kernel/idreg-override.c b/arch/arm64/kernel/idreg-override.c
index d8e606fe3c21..95133765ed29 100644
--- a/arch/arm64/kernel/idreg-override.c
+++ b/arch/arm64/kernel/idreg-override.c
@@ -17,7 +17,9 @@
#define FTR_DESC_NAME_LEN 20
#define FTR_DESC_FIELD_LEN 10
#define FTR_ALIAS_NAME_LEN 30
-#define FTR_ALIAS_OPTION_LEN 80
+#define FTR_ALIAS_OPTION_LEN 116
+
+static u64 __boot_status __initdata;
struct ftr_set_desc {
char name[FTR_DESC_NAME_LEN];
@@ -25,10 +27,13 @@ struct ftr_set_desc {
struct {
char name[FTR_DESC_FIELD_LEN];
u8 shift;
+ u8 width;
bool (*filter)(u64 val);
} fields[];
};
+#define FIELD(n, s, f) { .name = n, .shift = s, .width = 4, .filter = f }
+
static bool __init mmfr1_vh_filter(u64 val)
{
/*
@@ -37,24 +42,65 @@ static bool __init mmfr1_vh_filter(u64 val)
* the user was trying to force nVHE on us, proceed with
* attitude adjustment.
*/
- return !(is_kernel_in_hyp_mode() && val == 0);
+ return !(__boot_status == (BOOT_CPU_FLAG_E2H | BOOT_CPU_MODE_EL2) &&
+ val == 0);
}
static const struct ftr_set_desc mmfr1 __initconst = {
.name = "id_aa64mmfr1",
.override = &id_aa64mmfr1_override,
.fields = {
- { "vh", ID_AA64MMFR1_VHE_SHIFT, mmfr1_vh_filter },
+ FIELD("vh", ID_AA64MMFR1_EL1_VH_SHIFT, mmfr1_vh_filter),
+ {}
+ },
+};
+
+static bool __init pfr0_sve_filter(u64 val)
+{
+ /*
+ * Disabling SVE also means disabling all the features that
+ * are associated with it. The easiest way to do it is just to
+ * override id_aa64zfr0_el1 to be 0.
+ */
+ if (!val) {
+ id_aa64zfr0_override.val = 0;
+ id_aa64zfr0_override.mask = GENMASK(63, 0);
+ }
+
+ return true;
+}
+
+static const struct ftr_set_desc pfr0 __initconst = {
+ .name = "id_aa64pfr0",
+ .override = &id_aa64pfr0_override,
+ .fields = {
+ FIELD("sve", ID_AA64PFR0_EL1_SVE_SHIFT, pfr0_sve_filter),
{}
},
};
+static bool __init pfr1_sme_filter(u64 val)
+{
+ /*
+ * Similarly to SVE, disabling SME also means disabling all
+ * the features that are associated with it. Just set
+ * id_aa64smfr0_el1 to 0 and don't look back.
+ */
+ if (!val) {
+ id_aa64smfr0_override.val = 0;
+ id_aa64smfr0_override.mask = GENMASK(63, 0);
+ }
+
+ return true;
+}
+
static const struct ftr_set_desc pfr1 __initconst = {
.name = "id_aa64pfr1",
.override = &id_aa64pfr1_override,
.fields = {
- { "bt", ID_AA64PFR1_BT_SHIFT },
- { "mte", ID_AA64PFR1_MTE_SHIFT},
+ FIELD("bt", ID_AA64PFR1_EL1_BT_SHIFT, NULL ),
+ FIELD("mte", ID_AA64PFR1_EL1_MTE_SHIFT, NULL),
+ FIELD("sme", ID_AA64PFR1_EL1_SME_SHIFT, pfr1_sme_filter),
{}
},
};
@@ -63,10 +109,30 @@ static const struct ftr_set_desc isar1 __initconst = {
.name = "id_aa64isar1",
.override = &id_aa64isar1_override,
.fields = {
- { "gpi", ID_AA64ISAR1_GPI_SHIFT },
- { "gpa", ID_AA64ISAR1_GPA_SHIFT },
- { "api", ID_AA64ISAR1_API_SHIFT },
- { "apa", ID_AA64ISAR1_APA_SHIFT },
+ FIELD("gpi", ID_AA64ISAR1_EL1_GPI_SHIFT, NULL),
+ FIELD("gpa", ID_AA64ISAR1_EL1_GPA_SHIFT, NULL),
+ FIELD("api", ID_AA64ISAR1_EL1_API_SHIFT, NULL),
+ FIELD("apa", ID_AA64ISAR1_EL1_APA_SHIFT, NULL),
+ {}
+ },
+};
+
+static const struct ftr_set_desc isar2 __initconst = {
+ .name = "id_aa64isar2",
+ .override = &id_aa64isar2_override,
+ .fields = {
+ FIELD("gpa3", ID_AA64ISAR2_EL1_GPA3_SHIFT, NULL),
+ FIELD("apa3", ID_AA64ISAR2_EL1_APA3_SHIFT, NULL),
+ {}
+ },
+};
+
+static const struct ftr_set_desc smfr0 __initconst = {
+ .name = "id_aa64smfr0",
+ .override = &id_aa64smfr0_override,
+ .fields = {
+ /* FA64 is a one bit field... :-/ */
+ { "fa64", ID_AA64SMFR0_EL1_FA64_SHIFT, 1, },
{}
},
};
@@ -79,15 +145,18 @@ static const struct ftr_set_desc kaslr __initconst = {
.override = &kaslr_feature_override,
#endif
.fields = {
- { "disabled", 0 },
+ FIELD("disabled", 0, NULL),
{}
},
};
static const struct ftr_set_desc * const regs[] __initconst = {
&mmfr1,
+ &pfr0,
&pfr1,
&isar1,
+ &isar2,
+ &smfr0,
&kaslr,
};
@@ -97,10 +166,13 @@ static const struct {
} aliases[] __initconst = {
{ "kvm-arm.mode=nvhe", "id_aa64mmfr1.vh=0" },
{ "kvm-arm.mode=protected", "id_aa64mmfr1.vh=0" },
+ { "arm64.nosve", "id_aa64pfr0.sve=0 id_aa64pfr1.sme=0" },
+ { "arm64.nosme", "id_aa64pfr1.sme=0" },
{ "arm64.nobti", "id_aa64pfr1.bt=0" },
{ "arm64.nopauth",
"id_aa64isar1.gpi=0 id_aa64isar1.gpa=0 "
- "id_aa64isar1.api=0 id_aa64isar1.apa=0" },
+ "id_aa64isar1.api=0 id_aa64isar1.apa=0 "
+ "id_aa64isar2.gpa3=0 id_aa64isar2.apa3=0" },
{ "arm64.nomte", "id_aa64pfr1.mte=0" },
{ "nokaslr", "kaslr.disabled=1" },
};
@@ -132,7 +204,8 @@ static void __init match_options(const char *cmdline)
for (f = 0; strlen(regs[i]->fields[f].name); f++) {
u64 shift = regs[i]->fields[f].shift;
- u64 mask = 0xfUL << shift;
+ u64 width = regs[i]->fields[f].width ?: 4;
+ u64 mask = GENMASK_ULL(shift + width - 1, shift);
u64 v;
if (find_field(cmdline, regs[i], f, &v))
@@ -140,7 +213,7 @@ static void __init match_options(const char *cmdline)
/*
* If an override gets filtered out, advertise
- * it by setting the value to 0xf, but
+ * it by setting the value to the all-ones while
* clearing the mask... Yes, this is fragile.
*/
if (regs[i]->fields[f].filter &&
@@ -222,9 +295,9 @@ static __init void parse_cmdline(void)
}
/* Keep checkers quiet */
-void init_feature_override(void);
+void init_feature_override(u64 boot_status);
-asmlinkage void __init init_feature_override(void)
+asmlinkage void __init init_feature_override(u64 boot_status)
{
int i;
@@ -235,6 +308,8 @@ asmlinkage void __init init_feature_override(void)
}
}
+ __boot_status = boot_status;
+
parse_cmdline();
for (i = 0; i < ARRAY_SIZE(regs); i++) {