*/
#include <linux/init.h>
#include <linux/utsname.h>
+#include <linux/cpu.h>
+#include <linux/smp.h>
+#include <linux/nospec.h>
+#include <linux/prctl.h>
+
+#include <asm/spec-ctrl.h>
+#include <asm/cmdline.h>
#include <asm/bugs.h>
#include <asm/processor.h>
#include <asm/processor-flags.h>
#include <asm/alternative.h>
#include <asm/pgtable.h>
#include <asm/set_memory.h>
+#include <asm/intel-family.h>
+
+static void __init spectre_v2_select_mitigation(void);
+static void __init ssb_select_mitigation(void);
+
+/*
+ * Our boot-time value of the SPEC_CTRL MSR. We read it once so that any
+ * writes to SPEC_CTRL contain whatever reserved bits have been set.
+ */
+u64 __ro_after_init x86_spec_ctrl_base;
+
+/*
+ * The vendor and possibly platform specific bits which can be modified in
+ * x86_spec_ctrl_base.
+ */
+static u64 __ro_after_init x86_spec_ctrl_mask = ~SPEC_CTRL_IBRS;
+
+/*
+ * AMD specific MSR info for Speculative Store Bypass control.
+ * x86_amd_ls_cfg_ssbd_mask is initialized in identify_boot_cpu().
+ */
+u64 __ro_after_init x86_amd_ls_cfg_base;
+u64 __ro_after_init x86_amd_ls_cfg_ssbd_mask;
void __init check_bugs(void)
{
print_cpu_info(&boot_cpu_data);
}
+ /*
+ * Read the SPEC_CTRL MSR to account for reserved bits which may
+ * have unknown values. AMD64_LS_CFG MSR is cached in the early AMD
+ * init code as it is not enumerated and depends on the family.
+ */
+ if (boot_cpu_has(X86_FEATURE_MSR_SPEC_CTRL))
+ rdmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base);
+
+ /* Select the proper spectre mitigation before patching alternatives */
+ spectre_v2_select_mitigation();
+
+ /*
+ * Select proper mitigation for any exposure to the Speculative Store
+ * Bypass vulnerability.
+ */
+ ssb_select_mitigation();
+
#ifdef CONFIG_X86_32
/*
* Check whether we are able to run this kernel safely on SMP.
set_memory_4k((unsigned long)__va(0), 1);
#endif
}
+
+/* The kernel command line selection */
+enum spectre_v2_mitigation_cmd {
+ SPECTRE_V2_CMD_NONE,
+ SPECTRE_V2_CMD_AUTO,
+ SPECTRE_V2_CMD_FORCE,
+ SPECTRE_V2_CMD_RETPOLINE,
+ SPECTRE_V2_CMD_RETPOLINE_GENERIC,
+ SPECTRE_V2_CMD_RETPOLINE_AMD,
+};
+
+static const char *spectre_v2_strings[] = {
+ [SPECTRE_V2_NONE] = "Vulnerable",
+ [SPECTRE_V2_RETPOLINE_MINIMAL] = "Vulnerable: Minimal generic ASM retpoline",
+ [SPECTRE_V2_RETPOLINE_MINIMAL_AMD] = "Vulnerable: Minimal AMD ASM retpoline",
+ [SPECTRE_V2_RETPOLINE_GENERIC] = "Mitigation: Full generic retpoline",
+ [SPECTRE_V2_RETPOLINE_AMD] = "Mitigation: Full AMD retpoline",
+};
+
+#undef pr_fmt
+#define pr_fmt(fmt) "Spectre V2 mitigation: " fmt
+
+static enum spectre_v2_mitigation spectre_v2_enabled __ro_after_init =
+ SPECTRE_V2_NONE;
+
+void x86_spec_ctrl_set(u64 val)
+{
+ if (val & x86_spec_ctrl_mask)
+ WARN_ONCE(1, "SPEC_CTRL MSR value 0x%16llx is unknown.\n", val);
+ else
+ wrmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base | val);
+}
+EXPORT_SYMBOL_GPL(x86_spec_ctrl_set);
+
+u64 x86_spec_ctrl_get_default(void)
+{
+ u64 msrval = x86_spec_ctrl_base;
+
+ if (static_cpu_has(X86_FEATURE_SPEC_CTRL))
+ msrval |= ssbd_tif_to_spec_ctrl(current_thread_info()->flags);
+ return msrval;
+}
+EXPORT_SYMBOL_GPL(x86_spec_ctrl_get_default);
+
+void x86_spec_ctrl_set_guest(u64 guest_spec_ctrl)
+{
+ u64 host = x86_spec_ctrl_base;
+
+ /* Is MSR_SPEC_CTRL implemented ? */
+ if (!static_cpu_has(X86_FEATURE_MSR_SPEC_CTRL))
+ return;
+
+ /* SSBD controlled in MSR_SPEC_CTRL */
+ if (static_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD))
+ host |= ssbd_tif_to_spec_ctrl(current_thread_info()->flags);
+
+ if (host != guest_spec_ctrl)
+ wrmsrl(MSR_IA32_SPEC_CTRL, guest_spec_ctrl);
+}
+EXPORT_SYMBOL_GPL(x86_spec_ctrl_set_guest);
+
+void x86_spec_ctrl_restore_host(u64 guest_spec_ctrl)
+{
+ u64 host = x86_spec_ctrl_base;
+
+ /* Is MSR_SPEC_CTRL implemented ? */
+ if (!static_cpu_has(X86_FEATURE_MSR_SPEC_CTRL))
+ return;
+
+ /* SSBD controlled in MSR_SPEC_CTRL */
+ if (static_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD))
+ host |= ssbd_tif_to_spec_ctrl(current_thread_info()->flags);
+
+ if (host != guest_spec_ctrl)
+ wrmsrl(MSR_IA32_SPEC_CTRL, host);
+}
+EXPORT_SYMBOL_GPL(x86_spec_ctrl_restore_host);
+
+static void x86_amd_ssb_disable(void)
+{
+ u64 msrval = x86_amd_ls_cfg_base | x86_amd_ls_cfg_ssbd_mask;
+
+ if (boot_cpu_has(X86_FEATURE_LS_CFG_SSBD))
+ wrmsrl(MSR_AMD64_LS_CFG, msrval);
+}
+
+static void __init spec2_print_if_insecure(const char *reason)
+{
+ if (boot_cpu_has_bug(X86_BUG_SPECTRE_V2))
+ pr_info("%s\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);
+}
+
+static inline bool retp_compiler(void)
+{
+ return __is_defined(RETPOLINE);
+}
+
+static inline bool match_option(const char *arg, int arglen, const char *opt)
+{
+ int len = strlen(opt);
+
+ return len == arglen && !strncmp(arg, opt, len);
+}
+
+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")) {
+ return SPECTRE_V2_CMD_AUTO;
+ }
+ }
+
+ if (!cmdline_find_option_bool(boot_command_line, "nospectre_v2"))
+ return SPECTRE_V2_CMD_AUTO;
+disable:
+ spec2_print_if_insecure("disabled on command line.");
+ return SPECTRE_V2_CMD_NONE;
+}
+
+/* Check for Skylake-like CPUs (for RSB handling) */
+static bool __init is_skylake_era(void)
+{
+ if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
+ boot_cpu_data.x86 == 6) {
+ switch (boot_cpu_data.x86_model) {
+ case INTEL_FAM6_SKYLAKE_MOBILE:
+ case INTEL_FAM6_SKYLAKE_DESKTOP:
+ case INTEL_FAM6_SKYLAKE_X:
+ case INTEL_FAM6_KABYLAKE_MOBILE:
+ case INTEL_FAM6_KABYLAKE_DESKTOP:
+ return true;
+ }
+ }
+ return false;
+}
+
+static void __init spectre_v2_select_mitigation(void)
+{
+ enum spectre_v2_mitigation_cmd cmd = spectre_v2_parse_cmdline();
+ enum spectre_v2_mitigation mode = SPECTRE_V2_NONE;
+
+ /*
+ * If the CPU is not affected and the command line mode is NONE or AUTO
+ * then nothing to do.
+ */
+ if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V2) &&
+ (cmd == SPECTRE_V2_CMD_NONE || cmd == SPECTRE_V2_CMD_AUTO))
+ return;
+
+ switch (cmd) {
+ case SPECTRE_V2_CMD_NONE:
+ return;
+
+ case SPECTRE_V2_CMD_FORCE:
+ /* FALLTRHU */
+ case SPECTRE_V2_CMD_AUTO:
+ goto retpoline_auto;
+
+ case SPECTRE_V2_CMD_RETPOLINE_AMD:
+ if (IS_ENABLED(CONFIG_RETPOLINE))
+ goto retpoline_amd;
+ break;
+ case SPECTRE_V2_CMD_RETPOLINE_GENERIC:
+ if (IS_ENABLED(CONFIG_RETPOLINE))
+ goto retpoline_generic;
+ break;
+ case SPECTRE_V2_CMD_RETPOLINE:
+ if (IS_ENABLED(CONFIG_RETPOLINE))
+ goto retpoline_auto;
+ break;
+ }
+ pr_err("kernel not compiled with retpoline; no mitigation available!");
+ return;
+
+retpoline_auto:
+ if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
+ retpoline_amd:
+ if (!boot_cpu_has(X86_FEATURE_LFENCE_RDTSC)) {
+ pr_err("LFENCE not serializing. Switching to generic retpoline\n");
+ goto retpoline_generic;
+ }
+ mode = retp_compiler() ? SPECTRE_V2_RETPOLINE_AMD :
+ SPECTRE_V2_RETPOLINE_MINIMAL_AMD;
+ setup_force_cpu_cap(X86_FEATURE_RETPOLINE_AMD);
+ setup_force_cpu_cap(X86_FEATURE_RETPOLINE);
+ } else {
+ retpoline_generic:
+ mode = retp_compiler() ? SPECTRE_V2_RETPOLINE_GENERIC :
+ SPECTRE_V2_RETPOLINE_MINIMAL;
+ setup_force_cpu_cap(X86_FEATURE_RETPOLINE);
+ }
+
+ spectre_v2_enabled = mode;
+ pr_info("%s\n", spectre_v2_strings[mode]);
+
+ pr_info("Speculation control IBPB %s IBRS %s",
+ ibpb_supported ? "supported" : "not-supported",
+ ibrs_supported ? "supported" : "not-supported");
+
+ /*
+ * If we have a full retpoline mode and then disable IBPB in kernel mode
+ * we do not require both.
+ */
+ if (mode == SPECTRE_V2_RETPOLINE_AMD ||
+ mode == SPECTRE_V2_RETPOLINE_GENERIC)
+ {
+ if (ibrs_supported) {
+ pr_info("Retpoline compiled kernel. Defaulting IBRS to disabled");
+ set_ibrs_disabled();
+ if (!ibrs_inuse)
+ sysctl_ibrs_enabled = 0;
+ }
+ }
+
+ /*
+ * If neither SMEP or KPTI are available, there is a risk of
+ * hitting userspace addresses in the RSB after a context switch
+ * from a shallow call stack to a deeper one. To prevent this fill
+ * the entire RSB, even when using IBRS.
+ *
+ * Skylake era CPUs have a separate issue with *underflow* of the
+ * RSB, when they will predict 'ret' targets from the generic BTB.
+ * The proper mitigation for this is IBRS. If IBRS is not supported
+ * or deactivated in favour of retpolines the RSB fill on context
+ * switch is required.
+ */
+ if ((!boot_cpu_has(X86_FEATURE_PTI) &&
+ !boot_cpu_has(X86_FEATURE_SMEP)) || is_skylake_era()) {
+ setup_force_cpu_cap(X86_FEATURE_RSB_CTXSW);
+ pr_info("Filling RSB on context switch\n");
+ }
+}
+
+#undef pr_fmt
+#define pr_fmt(fmt) "Speculative Store Bypass: " fmt
+
+static enum ssb_mitigation ssb_mode __ro_after_init = SPEC_STORE_BYPASS_NONE;
+
+/* The kernel command line selection */
+enum ssb_mitigation_cmd {
+ SPEC_STORE_BYPASS_CMD_NONE,
+ SPEC_STORE_BYPASS_CMD_AUTO,
+ SPEC_STORE_BYPASS_CMD_ON,
+ SPEC_STORE_BYPASS_CMD_PRCTL,
+ SPEC_STORE_BYPASS_CMD_SECCOMP,
+};
+
+static const char *ssb_strings[] = {
+ [SPEC_STORE_BYPASS_NONE] = "Vulnerable",
+ [SPEC_STORE_BYPASS_DISABLE] = "Mitigation: Speculative Store Bypass disabled",
+ [SPEC_STORE_BYPASS_PRCTL] = "Mitigation: Speculative Store Bypass disabled via prctl",
+ [SPEC_STORE_BYPASS_SECCOMP] = "Mitigation: Speculative Store Bypass disabled via prctl and seccomp",
+};
+
+static const struct {
+ const char *option;
+ enum ssb_mitigation_cmd cmd;
+} ssb_mitigation_options[] = {
+ { "auto", SPEC_STORE_BYPASS_CMD_AUTO }, /* Platform decides */
+ { "on", SPEC_STORE_BYPASS_CMD_ON }, /* Disable Speculative Store Bypass */
+ { "off", SPEC_STORE_BYPASS_CMD_NONE }, /* Don't touch Speculative Store Bypass */
+ { "prctl", SPEC_STORE_BYPASS_CMD_PRCTL }, /* Disable Speculative Store Bypass via prctl */
+ { "seccomp", SPEC_STORE_BYPASS_CMD_SECCOMP }, /* Disable Speculative Store Bypass via prctl and seccomp */
+};
+
+static enum ssb_mitigation_cmd __init ssb_parse_cmdline(void)
+{
+ enum ssb_mitigation_cmd cmd = SPEC_STORE_BYPASS_CMD_AUTO;
+ char arg[20];
+ int ret, i;
+
+ if (cmdline_find_option_bool(boot_command_line, "nospec_store_bypass_disable")) {
+ return SPEC_STORE_BYPASS_CMD_NONE;
+ } else {
+ ret = cmdline_find_option(boot_command_line, "spec_store_bypass_disable",
+ arg, sizeof(arg));
+ if (ret < 0)
+ return SPEC_STORE_BYPASS_CMD_AUTO;
+
+ for (i = 0; i < ARRAY_SIZE(ssb_mitigation_options); i++) {
+ if (!match_option(arg, ret, ssb_mitigation_options[i].option))
+ continue;
+
+ cmd = ssb_mitigation_options[i].cmd;
+ break;
+ }
+
+ if (i >= ARRAY_SIZE(ssb_mitigation_options)) {
+ pr_err("unknown option (%s). Switching to AUTO select\n", arg);
+ return SPEC_STORE_BYPASS_CMD_AUTO;
+ }
+ }
+
+ return cmd;
+}
+
+static enum ssb_mitigation __init __ssb_select_mitigation(void)
+{
+ enum ssb_mitigation mode = SPEC_STORE_BYPASS_NONE;
+ enum ssb_mitigation_cmd cmd;
+
+ if (!boot_cpu_has(X86_FEATURE_SSBD))
+ return mode;
+
+ cmd = ssb_parse_cmdline();
+ if (!boot_cpu_has_bug(X86_BUG_SPEC_STORE_BYPASS) &&
+ (cmd == SPEC_STORE_BYPASS_CMD_NONE ||
+ cmd == SPEC_STORE_BYPASS_CMD_AUTO))
+ return mode;
+
+ switch (cmd) {
+ case SPEC_STORE_BYPASS_CMD_AUTO:
+ case SPEC_STORE_BYPASS_CMD_SECCOMP:
+ /*
+ * Choose prctl+seccomp as the default mode if seccomp is
+ * enabled.
+ */
+ if (IS_ENABLED(CONFIG_SECCOMP))
+ mode = SPEC_STORE_BYPASS_SECCOMP;
+ else
+ mode = SPEC_STORE_BYPASS_PRCTL;
+ break;
+ case SPEC_STORE_BYPASS_CMD_ON:
+ mode = SPEC_STORE_BYPASS_DISABLE;
+ break;
+ case SPEC_STORE_BYPASS_CMD_PRCTL:
+ mode = SPEC_STORE_BYPASS_PRCTL;
+ break;
+ case SPEC_STORE_BYPASS_CMD_NONE:
+ break;
+ }
+
+ /*
+ * We have three CPU feature flags that are in play here:
+ * - X86_BUG_SPEC_STORE_BYPASS - CPU is susceptible.
+ * - X86_FEATURE_SSBD - CPU is able to turn off speculative store bypass
+ * - X86_FEATURE_SPEC_STORE_BYPASS_DISABLE - engage the mitigation
+ */
+ if (mode == SPEC_STORE_BYPASS_DISABLE) {
+ setup_force_cpu_cap(X86_FEATURE_SPEC_STORE_BYPASS_DISABLE);
+ /*
+ * Intel uses the SPEC CTRL MSR Bit(2) for this, while AMD uses
+ * a completely different MSR and bit dependent on family.
+ */
+ switch (boot_cpu_data.x86_vendor) {
+ case X86_VENDOR_INTEL:
+ x86_spec_ctrl_base |= SPEC_CTRL_SSBD;
+ x86_spec_ctrl_mask &= ~SPEC_CTRL_SSBD;
+ x86_spec_ctrl_set(SPEC_CTRL_SSBD);
+ break;
+ case X86_VENDOR_AMD:
+ x86_amd_ssb_disable();
+ break;
+ }
+ }
+
+ return mode;
+}
+
+static void ssb_select_mitigation(void)
+{
+ ssb_mode = __ssb_select_mitigation();
+
+ if (boot_cpu_has_bug(X86_BUG_SPEC_STORE_BYPASS))
+ pr_info("%s\n", ssb_strings[ssb_mode]);
+}
+
+#undef pr_fmt
+#define pr_fmt(fmt) "Speculation prctl: " fmt
+
+static int ssb_prctl_set(struct task_struct *task, unsigned long ctrl)
+{
+ bool update;
+
+ if (ssb_mode != SPEC_STORE_BYPASS_PRCTL &&
+ ssb_mode != SPEC_STORE_BYPASS_SECCOMP)
+ return -ENXIO;
+
+ switch (ctrl) {
+ case PR_SPEC_ENABLE:
+ /* If speculation is force disabled, enable is not allowed */
+ if (task_spec_ssb_force_disable(task))
+ return -EPERM;
+ task_clear_spec_ssb_disable(task);
+ update = test_and_clear_tsk_thread_flag(task, TIF_SSBD);
+ break;
+ case PR_SPEC_DISABLE:
+ task_set_spec_ssb_disable(task);
+ update = !test_and_set_tsk_thread_flag(task, TIF_SSBD);
+ break;
+ case PR_SPEC_FORCE_DISABLE:
+ task_set_spec_ssb_disable(task);
+ task_set_spec_ssb_force_disable(task);
+ update = !test_and_set_tsk_thread_flag(task, TIF_SSBD);
+ break;
+ default:
+ return -ERANGE;
+ }
+
+ /*
+ * If being set on non-current task, delay setting the CPU
+ * mitigation until it is next scheduled.
+ */
+ if (task == current && update)
+ speculative_store_bypass_update();
+
+ return 0;
+}
+
+int arch_prctl_spec_ctrl_set(struct task_struct *task, unsigned long which,
+ unsigned long ctrl)
+{
+ switch (which) {
+ case PR_SPEC_STORE_BYPASS:
+ return ssb_prctl_set(task, ctrl);
+ default:
+ return -ENODEV;
+ }
+}
+
+#ifdef CONFIG_SECCOMP
+void arch_seccomp_spec_mitigate(struct task_struct *task)
+{
+ if (ssb_mode == SPEC_STORE_BYPASS_SECCOMP)
+ ssb_prctl_set(task, PR_SPEC_FORCE_DISABLE);
+}
+#endif
+
+static int ssb_prctl_get(struct task_struct *task)
+{
+ switch (ssb_mode) {
+ case SPEC_STORE_BYPASS_DISABLE:
+ return PR_SPEC_DISABLE;
+ case SPEC_STORE_BYPASS_SECCOMP:
+ case SPEC_STORE_BYPASS_PRCTL:
+ if (task_spec_ssb_force_disable(task))
+ return PR_SPEC_PRCTL | PR_SPEC_FORCE_DISABLE;
+ if (task_spec_ssb_disable(task))
+ return PR_SPEC_PRCTL | PR_SPEC_DISABLE;
+ return PR_SPEC_PRCTL | PR_SPEC_ENABLE;
+ default:
+ if (boot_cpu_has_bug(X86_BUG_SPEC_STORE_BYPASS))
+ return PR_SPEC_ENABLE;
+ return PR_SPEC_NOT_AFFECTED;
+ }
+}
+
+int arch_prctl_spec_ctrl_get(struct task_struct *task, unsigned long which)
+{
+ switch (which) {
+ case PR_SPEC_STORE_BYPASS:
+ return ssb_prctl_get(task);
+ default:
+ return -ENODEV;
+ }
+}
+
+void x86_spec_ctrl_setup_ap(void)
+{
+ if (boot_cpu_has(X86_FEATURE_MSR_SPEC_CTRL))
+ x86_spec_ctrl_set(x86_spec_ctrl_base & ~x86_spec_ctrl_mask);
+
+ if (ssb_mode == SPEC_STORE_BYPASS_DISABLE)
+ x86_amd_ssb_disable();
+}
+
+#ifdef CONFIG_SYSFS
+static ssize_t cpu_show_common(struct device *dev, struct device_attribute *attr,
+ char *buf, unsigned int bug)
+{
+ if (!boot_cpu_has_bug(bug))
+ return sprintf(buf, "Not affected\n");
+
+ switch (bug) {
+ case X86_BUG_CPU_MELTDOWN:
+ if (boot_cpu_has(X86_FEATURE_PTI))
+ return sprintf(buf, "Mitigation: PTI\n");
+ break;
+
+ case X86_BUG_SPECTRE_V1:
+ if (osb_is_enabled)
+ return sprintf(buf, "Mitigation: OSB (observable speculation barrier, Intel v6)\n");
+
+ case X86_BUG_SPECTRE_V2:
+ return sprintf(buf, "%s%s\n", spectre_v2_strings[spectre_v2_enabled], ibpb_inuse ? ", IBPB (Intel v4)" : "");
+
+ case X86_BUG_SPEC_STORE_BYPASS:
+ return sprintf(buf, "%s\n", ssb_strings[ssb_mode]);
+
+ default:
+ break;
+ }
+
+ return sprintf(buf, "Vulnerable\n");
+}
+
+ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ return cpu_show_common(dev, attr, buf, X86_BUG_CPU_MELTDOWN);
+}
+
+ssize_t cpu_show_spectre_v1(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ return cpu_show_common(dev, attr, buf, X86_BUG_SPECTRE_V1);
+}
+
+ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ return cpu_show_common(dev, attr, buf, X86_BUG_SPECTRE_V2);
+}
+
+ssize_t cpu_show_spec_store_bypass(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ return cpu_show_common(dev, attr, buf, X86_BUG_SPEC_STORE_BYPASS);
+}
+#endif