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-rw-r--r--arch/arm64/kernel/idreg-override.c153
1 files changed, 95 insertions, 58 deletions
diff --git a/arch/arm64/kernel/idreg-override.c b/arch/arm64/kernel/idreg-override.c
index 3addc09f87..e30fd9e32e 100644
--- a/arch/arm64/kernel/idreg-override.c
+++ b/arch/arm64/kernel/idreg-override.c
@@ -21,14 +21,25 @@
static u64 __boot_status __initdata;
+// temporary __prel64 related definitions
+// to be removed when this code is moved under pi/
+
+#define __prel64_initconst __initconst
+
+#define PREL64(type, name) union { type *name; }
+
+#define prel64_pointer(__d) (__d)
+
+typedef bool filter_t(u64 val);
+
struct ftr_set_desc {
char name[FTR_DESC_NAME_LEN];
- struct arm64_ftr_override *override;
+ PREL64(struct arm64_ftr_override, override);
struct {
char name[FTR_DESC_FIELD_LEN];
u8 shift;
u8 width;
- bool (*filter)(u64 val);
+ PREL64(filter_t, filter);
} fields[];
};
@@ -46,7 +57,7 @@ static bool __init mmfr1_vh_filter(u64 val)
val == 0);
}
-static const struct ftr_set_desc mmfr1 __initconst = {
+static const struct ftr_set_desc mmfr1 __prel64_initconst = {
.name = "id_aa64mmfr1",
.override = &id_aa64mmfr1_override,
.fields = {
@@ -70,7 +81,7 @@ static bool __init pfr0_sve_filter(u64 val)
return true;
}
-static const struct ftr_set_desc pfr0 __initconst = {
+static const struct ftr_set_desc pfr0 __prel64_initconst = {
.name = "id_aa64pfr0",
.override = &id_aa64pfr0_override,
.fields = {
@@ -94,7 +105,7 @@ static bool __init pfr1_sme_filter(u64 val)
return true;
}
-static const struct ftr_set_desc pfr1 __initconst = {
+static const struct ftr_set_desc pfr1 __prel64_initconst = {
.name = "id_aa64pfr1",
.override = &id_aa64pfr1_override,
.fields = {
@@ -105,7 +116,7 @@ static const struct ftr_set_desc pfr1 __initconst = {
},
};
-static const struct ftr_set_desc isar1 __initconst = {
+static const struct ftr_set_desc isar1 __prel64_initconst = {
.name = "id_aa64isar1",
.override = &id_aa64isar1_override,
.fields = {
@@ -117,7 +128,7 @@ static const struct ftr_set_desc isar1 __initconst = {
},
};
-static const struct ftr_set_desc isar2 __initconst = {
+static const struct ftr_set_desc isar2 __prel64_initconst = {
.name = "id_aa64isar2",
.override = &id_aa64isar2_override,
.fields = {
@@ -128,7 +139,7 @@ static const struct ftr_set_desc isar2 __initconst = {
},
};
-static const struct ftr_set_desc smfr0 __initconst = {
+static const struct ftr_set_desc smfr0 __prel64_initconst = {
.name = "id_aa64smfr0",
.override = &id_aa64smfr0_override,
.fields = {
@@ -149,7 +160,7 @@ static bool __init hvhe_filter(u64 val)
ID_AA64MMFR1_EL1_VH_SHIFT));
}
-static const struct ftr_set_desc sw_features __initconst = {
+static const struct ftr_set_desc sw_features __prel64_initconst = {
.name = "arm64_sw",
.override = &arm64_sw_feature_override,
.fields = {
@@ -159,22 +170,23 @@ static const struct ftr_set_desc sw_features __initconst = {
},
};
-static const struct ftr_set_desc * const regs[] __initconst = {
- &mmfr1,
- &pfr0,
- &pfr1,
- &isar1,
- &isar2,
- &smfr0,
- &sw_features,
+static const
+PREL64(const struct ftr_set_desc, reg) regs[] __prel64_initconst = {
+ { &mmfr1 },
+ { &pfr0 },
+ { &pfr1 },
+ { &isar1 },
+ { &isar2 },
+ { &smfr0 },
+ { &sw_features },
};
static const struct {
char alias[FTR_ALIAS_NAME_LEN];
char feature[FTR_ALIAS_OPTION_LEN];
} aliases[] __initconst = {
- { "kvm-arm.mode=nvhe", "id_aa64mmfr1.vh=0" },
- { "kvm-arm.mode=protected", "id_aa64mmfr1.vh=0" },
+ { "kvm_arm.mode=nvhe", "id_aa64mmfr1.vh=0" },
+ { "kvm_arm.mode=protected", "id_aa64mmfr1.vh=0" },
{ "arm64.nosve", "id_aa64pfr0.sve=0" },
{ "arm64.nosme", "id_aa64pfr1.sme=0" },
{ "arm64.nobti", "id_aa64pfr1.bt=0" },
@@ -187,45 +199,61 @@ static const struct {
{ "nokaslr", "arm64_sw.nokaslr=1" },
};
-static int __init parse_nokaslr(char *unused)
+static int __init parse_hexdigit(const char *p, u64 *v)
{
- /* nokaslr param handling is done by early cpufeature code */
+ // skip "0x" if it comes next
+ if (p[0] == '0' && tolower(p[1]) == 'x')
+ p += 2;
+
+ // check whether the RHS is a single hex digit
+ if (!isxdigit(p[0]) || (p[1] && !isspace(p[1])))
+ return -EINVAL;
+
+ *v = tolower(*p) - (isdigit(*p) ? '0' : 'a' - 10);
return 0;
}
-early_param("nokaslr", parse_nokaslr);
-static int __init find_field(const char *cmdline,
+static int __init find_field(const char *cmdline, char *opt, int len,
const struct ftr_set_desc *reg, int f, u64 *v)
{
- char opt[FTR_DESC_NAME_LEN + FTR_DESC_FIELD_LEN + 2];
- int len;
+ int flen = strlen(reg->fields[f].name);
- len = snprintf(opt, ARRAY_SIZE(opt), "%s.%s=",
- reg->name, reg->fields[f].name);
+ // append '<fieldname>=' to obtain '<name>.<fieldname>='
+ memcpy(opt + len, reg->fields[f].name, flen);
+ len += flen;
+ opt[len++] = '=';
- if (!parameqn(cmdline, opt, len))
+ if (memcmp(cmdline, opt, len))
return -1;
- return kstrtou64(cmdline + len, 0, v);
+ return parse_hexdigit(cmdline + len, v);
}
static void __init match_options(const char *cmdline)
{
+ char opt[FTR_DESC_NAME_LEN + FTR_DESC_FIELD_LEN + 2];
int i;
for (i = 0; i < ARRAY_SIZE(regs); i++) {
+ const struct ftr_set_desc *reg = prel64_pointer(regs[i].reg);
+ struct arm64_ftr_override *override;
+ int len = strlen(reg->name);
int f;
- if (!regs[i]->override)
- continue;
+ override = prel64_pointer(reg->override);
- for (f = 0; strlen(regs[i]->fields[f].name); f++) {
- u64 shift = regs[i]->fields[f].shift;
- u64 width = regs[i]->fields[f].width ?: 4;
+ // set opt[] to '<name>.'
+ memcpy(opt, reg->name, len);
+ opt[len++] = '.';
+
+ for (f = 0; reg->fields[f].name[0] != '\0'; f++) {
+ u64 shift = reg->fields[f].shift;
+ u64 width = reg->fields[f].width ?: 4;
u64 mask = GENMASK_ULL(shift + width - 1, shift);
+ bool (*filter)(u64 val);
u64 v;
- if (find_field(cmdline, regs[i], f, &v))
+ if (find_field(cmdline, opt, len, reg, f, &v))
continue;
/*
@@ -233,16 +261,16 @@ static void __init match_options(const char *cmdline)
* it by setting the value to the all-ones while
* clearing the mask... Yes, this is fragile.
*/
- if (regs[i]->fields[f].filter &&
- !regs[i]->fields[f].filter(v)) {
- regs[i]->override->val |= mask;
- regs[i]->override->mask &= ~mask;
+ filter = prel64_pointer(reg->fields[f].filter);
+ if (filter && !filter(v)) {
+ override->val |= mask;
+ override->mask &= ~mask;
continue;
}
- regs[i]->override->val &= ~mask;
- regs[i]->override->val |= (v << shift) & mask;
- regs[i]->override->mask |= mask;
+ override->val &= ~mask;
+ override->val |= (v << shift) & mask;
+ override->mask |= mask;
return;
}
@@ -258,23 +286,29 @@ static __init void __parse_cmdline(const char *cmdline, bool parse_aliases)
cmdline = skip_spaces(cmdline);
- for (len = 0; cmdline[len] && !isspace(cmdline[len]); len++);
- if (!len)
+ /* terminate on "--" appearing on the command line by itself */
+ if (cmdline[0] == '-' && cmdline[1] == '-' && isspace(cmdline[2]))
return;
- len = min(len, ARRAY_SIZE(buf) - 1);
- memcpy(buf, cmdline, len);
- buf[len] = '\0';
-
- if (strcmp(buf, "--") == 0)
+ for (len = 0; cmdline[len] && !isspace(cmdline[len]); len++) {
+ if (len >= sizeof(buf) - 1)
+ break;
+ if (cmdline[len] == '-')
+ buf[len] = '_';
+ else
+ buf[len] = cmdline[len];
+ }
+ if (!len)
return;
+ buf[len] = 0;
+
cmdline += len;
match_options(buf);
for (i = 0; parse_aliases && i < ARRAY_SIZE(aliases); i++)
- if (parameq(buf, aliases[i].alias))
+ if (!memcmp(buf, aliases[i].alias, len + 1))
__parse_cmdline(aliases[i].feature, false);
} while (1);
}
@@ -316,13 +350,16 @@ void init_feature_override(u64 boot_status);
asmlinkage void __init init_feature_override(u64 boot_status)
{
+ struct arm64_ftr_override *override;
+ const struct ftr_set_desc *reg;
int i;
for (i = 0; i < ARRAY_SIZE(regs); i++) {
- if (regs[i]->override) {
- regs[i]->override->val = 0;
- regs[i]->override->mask = 0;
- }
+ reg = prel64_pointer(regs[i].reg);
+ override = prel64_pointer(reg->override);
+
+ override->val = 0;
+ override->mask = 0;
}
__boot_status = boot_status;
@@ -330,9 +367,9 @@ asmlinkage void __init init_feature_override(u64 boot_status)
parse_cmdline();
for (i = 0; i < ARRAY_SIZE(regs); i++) {
- if (regs[i]->override)
- dcache_clean_inval_poc((unsigned long)regs[i]->override,
- (unsigned long)regs[i]->override +
- sizeof(*regs[i]->override));
+ reg = prel64_pointer(regs[i].reg);
+ override = prel64_pointer(reg->override);
+ dcache_clean_inval_poc((unsigned long)override,
+ (unsigned long)(override + 1));
}
}