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-rw-r--r--arch/x86/kernel/alternative.c14
-rw-r--r--arch/x86/kernel/cpu/bugs.c122
-rw-r--r--arch/x86/kernel/cpu/mcheck/mce-inject.c5
-rw-r--r--arch/x86/kernel/cpu/microcode/amd.c17
-rw-r--r--arch/x86/kernel/cpu/perf_event.c4
-rw-r--r--arch/x86/kernel/head_32.S9
6 files changed, 106 insertions, 65 deletions
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index d6f375f1b928..89829c3d5a74 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -45,17 +45,6 @@ static int __init setup_noreplace_smp(char *str)
}
__setup("noreplace-smp", setup_noreplace_smp);
-#ifdef CONFIG_PARAVIRT
-static int __initdata_or_module noreplace_paravirt = 0;
-
-static int __init setup_noreplace_paravirt(char *str)
-{
- noreplace_paravirt = 1;
- return 1;
-}
-__setup("noreplace-paravirt", setup_noreplace_paravirt);
-#endif
-
#define DPRINTK(fmt, args...) \
do { \
if (debug_alternative) \
@@ -587,9 +576,6 @@ void __init_or_module apply_paravirt(struct paravirt_patch_site *start,
struct paravirt_patch_site *p;
char insnbuf[MAX_PATCH_LEN];
- if (noreplace_paravirt)
- return;
-
for (p = start; p < end; p++) {
unsigned int used;
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 8cacf62ec458..ecaf7c9baf75 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -10,6 +10,7 @@
#include <linux/init.h>
#include <linux/utsname.h>
#include <linux/cpu.h>
+#include <linux/module.h>
#include <asm/nospec-branch.h>
#include <asm/cmdline.h>
@@ -89,20 +90,42 @@ static const char *spectre_v2_strings[] = {
};
#undef pr_fmt
-#define pr_fmt(fmt) "Spectre V2 mitigation: " fmt
+#define pr_fmt(fmt) "Spectre V2 : " fmt
static enum spectre_v2_mitigation spectre_v2_enabled = SPECTRE_V2_NONE;
+
+#ifdef RETPOLINE
+static bool spectre_v2_bad_module;
+
+bool retpoline_module_ok(bool has_retpoline)
+{
+ if (spectre_v2_enabled == SPECTRE_V2_NONE || has_retpoline)
+ return true;
+
+ pr_err("System may be vulnerable to spectre v2\n");
+ spectre_v2_bad_module = true;
+ return false;
+}
+
+static inline const char *spectre_v2_module_string(void)
+{
+ return spectre_v2_bad_module ? " - vulnerable module loaded" : "";
+}
+#else
+static inline const char *spectre_v2_module_string(void) { return ""; }
+#endif
+
static void __init spec2_print_if_insecure(const char *reason)
{
if (boot_cpu_has_bug(X86_BUG_SPECTRE_V2))
- pr_info("%s\n", reason);
+ pr_info("%s selected on command line.\n", reason);
}
static void __init spec2_print_if_secure(const char *reason)
{
if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V2))
- pr_info("%s\n", reason);
+ pr_info("%s selected on command line.\n", reason);
}
static inline bool retp_compiler(void)
@@ -117,42 +140,68 @@ static inline bool match_option(const char *arg, int arglen, const char *opt)
return len == arglen && !strncmp(arg, opt, len);
}
+static const struct {
+ const char *option;
+ enum spectre_v2_mitigation_cmd cmd;
+ bool secure;
+} mitigation_options[] = {
+ { "off", SPECTRE_V2_CMD_NONE, false },
+ { "on", SPECTRE_V2_CMD_FORCE, true },
+ { "retpoline", SPECTRE_V2_CMD_RETPOLINE, false },
+ { "retpoline,amd", SPECTRE_V2_CMD_RETPOLINE_AMD, false },
+ { "retpoline,generic", SPECTRE_V2_CMD_RETPOLINE_GENERIC, false },
+ { "auto", SPECTRE_V2_CMD_AUTO, false },
+};
+
static enum spectre_v2_mitigation_cmd __init spectre_v2_parse_cmdline(void)
{
char arg[20];
- int ret;
-
- ret = cmdline_find_option(boot_command_line, "spectre_v2", arg,
- sizeof(arg));
- if (ret > 0) {
- if (match_option(arg, ret, "off")) {
- goto disable;
- } else if (match_option(arg, ret, "on")) {
- spec2_print_if_secure("force enabled on command line.");
- return SPECTRE_V2_CMD_FORCE;
- } else if (match_option(arg, ret, "retpoline")) {
- spec2_print_if_insecure("retpoline selected on command line.");
- return SPECTRE_V2_CMD_RETPOLINE;
- } else if (match_option(arg, ret, "retpoline,amd")) {
- if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD) {
- pr_err("retpoline,amd selected but CPU is not AMD. Switching to AUTO select\n");
- return SPECTRE_V2_CMD_AUTO;
- }
- spec2_print_if_insecure("AMD retpoline selected on command line.");
- return SPECTRE_V2_CMD_RETPOLINE_AMD;
- } else if (match_option(arg, ret, "retpoline,generic")) {
- spec2_print_if_insecure("generic retpoline selected on command line.");
- return SPECTRE_V2_CMD_RETPOLINE_GENERIC;
- } else if (match_option(arg, ret, "auto")) {
+ int ret, i;
+ enum spectre_v2_mitigation_cmd cmd = SPECTRE_V2_CMD_AUTO;
+
+ if (cmdline_find_option_bool(boot_command_line, "nospectre_v2"))
+ return SPECTRE_V2_CMD_NONE;
+ else {
+ ret = cmdline_find_option(boot_command_line, "spectre_v2", arg,
+ sizeof(arg));
+ if (ret < 0)
+ return SPECTRE_V2_CMD_AUTO;
+
+ for (i = 0; i < ARRAY_SIZE(mitigation_options); i++) {
+ if (!match_option(arg, ret, mitigation_options[i].option))
+ continue;
+ cmd = mitigation_options[i].cmd;
+ break;
+ }
+
+ if (i >= ARRAY_SIZE(mitigation_options)) {
+ pr_err("unknown option (%s). Switching to AUTO select\n",
+ mitigation_options[i].option);
return SPECTRE_V2_CMD_AUTO;
}
}
- if (!cmdline_find_option_bool(boot_command_line, "nospectre_v2"))
+ if ((cmd == SPECTRE_V2_CMD_RETPOLINE ||
+ cmd == SPECTRE_V2_CMD_RETPOLINE_AMD ||
+ cmd == SPECTRE_V2_CMD_RETPOLINE_GENERIC) &&
+ !IS_ENABLED(CONFIG_RETPOLINE)) {
+ pr_err("%s selected but not compiled in. Switching to AUTO select\n",
+ mitigation_options[i].option);
return SPECTRE_V2_CMD_AUTO;
-disable:
- spec2_print_if_insecure("disabled on command line.");
- return SPECTRE_V2_CMD_NONE;
+ }
+
+ if (cmd == SPECTRE_V2_CMD_RETPOLINE_AMD &&
+ boot_cpu_data.x86_vendor != X86_VENDOR_AMD) {
+ pr_err("retpoline,amd selected but CPU is not AMD. Switching to AUTO select\n");
+ return SPECTRE_V2_CMD_AUTO;
+ }
+
+ if (mitigation_options[i].secure)
+ spec2_print_if_secure(mitigation_options[i].option);
+ else
+ spec2_print_if_insecure(mitigation_options[i].option);
+
+ return cmd;
}
/* Check for Skylake-like CPUs (for RSB handling) */
@@ -190,10 +239,10 @@ static void __init spectre_v2_select_mitigation(void)
return;
case SPECTRE_V2_CMD_FORCE:
- /* FALLTRHU */
case SPECTRE_V2_CMD_AUTO:
- goto retpoline_auto;
-
+ if (IS_ENABLED(CONFIG_RETPOLINE))
+ goto retpoline_auto;
+ break;
case SPECTRE_V2_CMD_RETPOLINE_AMD:
if (IS_ENABLED(CONFIG_RETPOLINE))
goto retpoline_amd;
@@ -268,7 +317,7 @@ ssize_t cpu_show_spectre_v1(struct device *dev,
{
if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V1))
return sprintf(buf, "Not affected\n");
- return sprintf(buf, "Vulnerable\n");
+ return sprintf(buf, "Mitigation: __user pointer sanitization\n");
}
ssize_t cpu_show_spectre_v2(struct device *dev,
@@ -277,6 +326,7 @@ ssize_t cpu_show_spectre_v2(struct device *dev,
if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V2))
return sprintf(buf, "Not affected\n");
- return sprintf(buf, "%s\n", spectre_v2_strings[spectre_v2_enabled]);
+ return sprintf(buf, "%s%s\n", spectre_v2_strings[spectre_v2_enabled],
+ spectre_v2_module_string());
}
#endif
diff --git a/arch/x86/kernel/cpu/mcheck/mce-inject.c b/arch/x86/kernel/cpu/mcheck/mce-inject.c
index 4cfba4371a71..101bfae369e1 100644
--- a/arch/x86/kernel/cpu/mcheck/mce-inject.c
+++ b/arch/x86/kernel/cpu/mcheck/mce-inject.c
@@ -152,7 +152,6 @@ static void raise_mce(struct mce *m)
if (context == MCJ_CTX_RANDOM)
return;
-#ifdef CONFIG_X86_LOCAL_APIC
if (m->inject_flags & (MCJ_IRQ_BROADCAST | MCJ_NMI_BROADCAST)) {
unsigned long start;
int cpu;
@@ -193,9 +192,7 @@ static void raise_mce(struct mce *m)
raise_local();
put_cpu();
put_online_cpus();
- } else
-#endif
- {
+ } else {
preempt_disable();
raise_local();
preempt_enable();
diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c
index 2a0f44d225fe..6da6f9cd6d2d 100644
--- a/arch/x86/kernel/cpu/microcode/amd.c
+++ b/arch/x86/kernel/cpu/microcode/amd.c
@@ -131,6 +131,9 @@ static size_t compute_container_size(u8 *data, u32 total_size)
return size;
}
+static enum ucode_state
+load_microcode_amd(bool save, u8 family, const u8 *data, size_t size);
+
/*
* Early load occurs before we can vmalloc(). So we look for the microcode
* patch container file in initrd, traverse equivalent cpu table, look for a
@@ -438,7 +441,7 @@ int __init save_microcode_in_initrd_amd(void)
eax = cpuid_eax(0x00000001);
eax = ((eax >> 8) & 0xf) + ((eax >> 20) & 0xff);
- ret = load_microcode_amd(smp_processor_id(), eax, container, container_size);
+ ret = load_microcode_amd(true, eax, container, container_size);
if (ret != UCODE_OK)
retval = -EINVAL;
@@ -854,7 +857,8 @@ static enum ucode_state __load_microcode_amd(u8 family, const u8 *data,
return UCODE_OK;
}
-enum ucode_state load_microcode_amd(int cpu, u8 family, const u8 *data, size_t size)
+static enum ucode_state
+load_microcode_amd(bool save, u8 family, const u8 *data, size_t size)
{
enum ucode_state ret;
@@ -868,8 +872,8 @@ enum ucode_state load_microcode_amd(int cpu, u8 family, const u8 *data, size_t s
#ifdef CONFIG_X86_32
/* save BSP's matching patch for early load */
- if (cpu_data(cpu).cpu_index == boot_cpu_data.cpu_index) {
- struct ucode_patch *p = find_patch(cpu);
+ if (save) {
+ struct ucode_patch *p = find_patch(0);
if (p) {
memset(amd_ucode_patch, 0, PATCH_MAX_SIZE);
memcpy(amd_ucode_patch, p->data, min_t(u32, ksize(p->data),
@@ -901,11 +905,12 @@ static enum ucode_state request_microcode_amd(int cpu, struct device *device,
{
char fw_name[36] = "amd-ucode/microcode_amd.bin";
struct cpuinfo_x86 *c = &cpu_data(cpu);
+ bool bsp = c->cpu_index == boot_cpu_data.cpu_index;
enum ucode_state ret = UCODE_NFOUND;
const struct firmware *fw;
/* reload ucode container only on the boot cpu */
- if (!refresh_fw || c->cpu_index != boot_cpu_data.cpu_index)
+ if (!refresh_fw || !bsp)
return UCODE_OK;
if (c->x86 >= 0x15)
@@ -922,7 +927,7 @@ static enum ucode_state request_microcode_amd(int cpu, struct device *device,
goto fw_release;
}
- ret = load_microcode_amd(cpu, c->x86, fw->data, fw->size);
+ ret = load_microcode_amd(bsp, c->x86, fw->data, fw->size);
fw_release:
release_firmware(fw);
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index 5b2f2306fbcc..b52a8d08ab36 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -188,8 +188,8 @@ static void release_pmc_hardware(void) {}
static bool check_hw_exists(void)
{
- u64 val, val_fail, val_new= ~0;
- int i, reg, reg_fail, ret = 0;
+ u64 val, val_fail = -1, val_new= ~0;
+ int i, reg, reg_fail = -1, ret = 0;
int bios_fail = 0;
int reg_safe = -1;
diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S
index 8f1a3f443f7d..70284d38fdc2 100644
--- a/arch/x86/kernel/head_32.S
+++ b/arch/x86/kernel/head_32.S
@@ -669,14 +669,17 @@ __PAGE_ALIGNED_BSS
initial_pg_pmd:
.fill 1024*KPMDS,4,0
#else
-ENTRY(initial_page_table)
+.globl initial_page_table
+initial_page_table:
.fill 1024,4,0
#endif
initial_pg_fixmap:
.fill 1024,4,0
-ENTRY(empty_zero_page)
+.globl empty_zero_page
+empty_zero_page:
.fill 4096,1,0
-ENTRY(swapper_pg_dir)
+.globl swapper_pg_dir
+swapper_pg_dir:
.fill 1024,4,0
/*