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-rw-r--r--arch/arm64/include/asm/cpufeature.h6
-rw-r--r--arch/arm64/include/asm/kvm_host.h17
-rw-r--r--arch/arm64/include/asm/processor.h1
-rw-r--r--arch/arm64/include/asm/spectre.h27
-rw-r--r--arch/arm64/kernel/cpu_errata.c236
-rw-r--r--arch/arm64/kernel/proton-pack.c288
-rw-r--r--arch/arm64/kvm/hypercalls.c8
-rw-r--r--arch/arm64/kvm/psci.c8
8 files changed, 327 insertions, 264 deletions
diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h
index 851d144527ed..3b48aa121cee 100644
--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -698,12 +698,6 @@ static inline bool system_supports_tlb_range(void)
cpus_have_const_cap(ARM64_HAS_TLB_RANGE);
}
-#define ARM64_BP_HARDEN_UNKNOWN -1
-#define ARM64_BP_HARDEN_WA_NEEDED 0
-#define ARM64_BP_HARDEN_NOT_REQUIRED 1
-
-int get_spectre_v2_workaround_state(void);
-
#define ARM64_SSBD_UNKNOWN -1
#define ARM64_SSBD_FORCE_DISABLE 0
#define ARM64_SSBD_KERNEL 1
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index e52c927aade5..59f6cff0f0cb 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -631,23 +631,6 @@ static inline void kvm_set_pmu_events(u32 set, struct perf_event_attr *attr) {}
static inline void kvm_clr_pmu_events(u32 clr) {}
#endif
-#define KVM_BP_HARDEN_UNKNOWN -1
-#define KVM_BP_HARDEN_WA_NEEDED 0
-#define KVM_BP_HARDEN_NOT_REQUIRED 1
-
-static inline int kvm_arm_harden_branch_predictor(void)
-{
- switch (get_spectre_v2_workaround_state()) {
- case ARM64_BP_HARDEN_WA_NEEDED:
- return KVM_BP_HARDEN_WA_NEEDED;
- case ARM64_BP_HARDEN_NOT_REQUIRED:
- return KVM_BP_HARDEN_NOT_REQUIRED;
- case ARM64_BP_HARDEN_UNKNOWN:
- default:
- return KVM_BP_HARDEN_UNKNOWN;
- }
-}
-
#define KVM_SSBD_UNKNOWN -1
#define KVM_SSBD_FORCE_DISABLE 0
#define KVM_SSBD_KERNEL 1
diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h
index 240fe5e5b720..436ab1549ec6 100644
--- a/arch/arm64/include/asm/processor.h
+++ b/arch/arm64/include/asm/processor.h
@@ -38,6 +38,7 @@
#include <asm/pgtable-hwdef.h>
#include <asm/pointer_auth.h>
#include <asm/ptrace.h>
+#include <asm/spectre.h>
#include <asm/types.h>
/*
diff --git a/arch/arm64/include/asm/spectre.h b/arch/arm64/include/asm/spectre.h
new file mode 100644
index 000000000000..b776abe28dff
--- /dev/null
+++ b/arch/arm64/include/asm/spectre.h
@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Interface for managing mitigations for Spectre vulnerabilities.
+ *
+ * Copyright (C) 2020 Google LLC
+ * Author: Will Deacon <will@kernel.org>
+ */
+
+#ifndef __ASM_SPECTRE_H
+#define __ASM_SPECTRE_H
+
+#include <asm/cpufeature.h>
+
+/* Watch out, ordering is important here. */
+enum mitigation_state {
+ SPECTRE_UNAFFECTED,
+ SPECTRE_MITIGATED,
+ SPECTRE_VULNERABLE,
+};
+
+struct task_struct;
+
+enum mitigation_state arm64_get_spectre_v2_state(void);
+bool has_spectre_v2(const struct arm64_cpu_capabilities *cap, int scope);
+void spectre_v2_enable_mitigation(const struct arm64_cpu_capabilities *__unused);
+
+#endif /* __ASM_SPECTRE_H */
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index 5eb9a9126dc4..4103391f51b5 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -106,145 +106,6 @@ cpu_enable_trap_ctr_access(const struct arm64_cpu_capabilities *cap)
sysreg_clear_set(sctlr_el1, SCTLR_EL1_UCT, 0);
}
-atomic_t arm64_el2_vector_last_slot = ATOMIC_INIT(-1);
-
-#include <asm/mmu_context.h>
-#include <asm/cacheflush.h>
-
-DEFINE_PER_CPU_READ_MOSTLY(struct bp_hardening_data, bp_hardening_data);
-
-#ifdef CONFIG_RANDOMIZE_BASE
-static void __copy_hyp_vect_bpi(int slot, const char *hyp_vecs_start,
- const char *hyp_vecs_end)
-{
- void *dst = lm_alias(__bp_harden_hyp_vecs + slot * SZ_2K);
- int i;
-
- for (i = 0; i < SZ_2K; i += 0x80)
- memcpy(dst + i, hyp_vecs_start, hyp_vecs_end - hyp_vecs_start);
-
- __flush_icache_range((uintptr_t)dst, (uintptr_t)dst + SZ_2K);
-}
-
-static void install_bp_hardening_cb(bp_hardening_cb_t fn)
-{
- static DEFINE_RAW_SPINLOCK(bp_lock);
- int cpu, slot = -1;
- const char *hyp_vecs_start = __smccc_workaround_1_smc;
- const char *hyp_vecs_end = __smccc_workaround_1_smc +
- __SMCCC_WORKAROUND_1_SMC_SZ;
-
- /*
- * detect_harden_bp_fw() passes NULL for the hyp_vecs start/end if
- * we're a guest. Skip the hyp-vectors work.
- */
- if (!is_hyp_mode_available()) {
- __this_cpu_write(bp_hardening_data.fn, fn);
- return;
- }
-
- raw_spin_lock(&bp_lock);
- for_each_possible_cpu(cpu) {
- if (per_cpu(bp_hardening_data.fn, cpu) == fn) {
- slot = per_cpu(bp_hardening_data.hyp_vectors_slot, cpu);
- break;
- }
- }
-
- if (slot == -1) {
- slot = atomic_inc_return(&arm64_el2_vector_last_slot);
- BUG_ON(slot >= BP_HARDEN_EL2_SLOTS);
- __copy_hyp_vect_bpi(slot, hyp_vecs_start, hyp_vecs_end);
- }
-
- __this_cpu_write(bp_hardening_data.hyp_vectors_slot, slot);
- __this_cpu_write(bp_hardening_data.fn, fn);
- raw_spin_unlock(&bp_lock);
-}
-#else
-static void install_bp_hardening_cb(bp_hardening_cb_t fn)
-{
- __this_cpu_write(bp_hardening_data.fn, fn);
-}
-#endif /* CONFIG_RANDOMIZE_BASE */
-
-#include <linux/arm-smccc.h>
-
-static void __maybe_unused call_smc_arch_workaround_1(void)
-{
- arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_1, NULL);
-}
-
-static void call_hvc_arch_workaround_1(void)
-{
- arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_WORKAROUND_1, NULL);
-}
-
-static void qcom_link_stack_sanitization(void)
-{
- u64 tmp;
-
- asm volatile("mov %0, x30 \n"
- ".rept 16 \n"
- "bl . + 4 \n"
- ".endr \n"
- "mov x30, %0 \n"
- : "=&r" (tmp));
-}
-
-static bool __nospectre_v2;
-static int __init parse_nospectre_v2(char *str)
-{
- __nospectre_v2 = true;
- return 0;
-}
-early_param("nospectre_v2", parse_nospectre_v2);
-
-/*
- * -1: No workaround
- * 0: No workaround required
- * 1: Workaround installed
- */
-static int detect_harden_bp_fw(void)
-{
- bp_hardening_cb_t cb;
- struct arm_smccc_res res;
- u32 midr = read_cpuid_id();
-
- arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
- ARM_SMCCC_ARCH_WORKAROUND_1, &res);
-
- switch ((int)res.a0) {
- case 1:
- /* Firmware says we're just fine */
- return 0;
- case 0:
- break;
- default:
- return -1;
- }
-
- switch (arm_smccc_1_1_get_conduit()) {
- case SMCCC_CONDUIT_HVC:
- cb = call_hvc_arch_workaround_1;
- break;
-
- case SMCCC_CONDUIT_SMC:
- cb = call_smc_arch_workaround_1;
- break;
-
- default:
- return -1;
- }
-
- if (((midr & MIDR_CPU_MODEL_MASK) == MIDR_QCOM_FALKOR) ||
- ((midr & MIDR_CPU_MODEL_MASK) == MIDR_QCOM_FALKOR_V1))
- cb = qcom_link_stack_sanitization;
-
- install_bp_hardening_cb(cb);
- return 1;
-}
-
DEFINE_PER_CPU_READ_MOSTLY(u64, arm64_ssbd_callback_required);
int ssbd_state __read_mostly = ARM64_SSBD_KERNEL;
@@ -508,83 +369,6 @@ cpu_enable_cache_maint_trap(const struct arm64_cpu_capabilities *__unused)
.type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, \
CAP_MIDR_RANGE_LIST(midr_list)
-/* Track overall mitigation state. We are only mitigated if all cores are ok */
-static bool __hardenbp_enab = true;
-static bool __spectrev2_safe = true;
-
-int get_spectre_v2_workaround_state(void)
-{
- if (__spectrev2_safe)
- return ARM64_BP_HARDEN_NOT_REQUIRED;
-
- if (!__hardenbp_enab)
- return ARM64_BP_HARDEN_UNKNOWN;
-
- return ARM64_BP_HARDEN_WA_NEEDED;
-}
-
-/*
- * List of CPUs that do not need any Spectre-v2 mitigation at all.
- */
-static const struct midr_range spectre_v2_safe_list[] = {
- MIDR_ALL_VERSIONS(MIDR_CORTEX_A35),
- MIDR_ALL_VERSIONS(MIDR_CORTEX_A53),
- MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
- MIDR_ALL_VERSIONS(MIDR_BRAHMA_B53),
- MIDR_ALL_VERSIONS(MIDR_HISI_TSV110),
- MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_3XX_SILVER),
- MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER),
- { /* sentinel */ }
-};
-
-/*
- * Track overall bp hardening for all heterogeneous cores in the machine.
- * We are only considered "safe" if all booted cores are known safe.
- */
-static bool __maybe_unused
-check_branch_predictor(const struct arm64_cpu_capabilities *entry, int scope)
-{
- int need_wa;
-
- WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible());
-
- /* If the CPU has CSV2 set, we're safe */
- if (cpuid_feature_extract_unsigned_field(read_cpuid(ID_AA64PFR0_EL1),
- ID_AA64PFR0_CSV2_SHIFT))
- return false;
-
- /* Alternatively, we have a list of unaffected CPUs */
- if (is_midr_in_range_list(read_cpuid_id(), spectre_v2_safe_list))
- return false;
-
- /* Fallback to firmware detection */
- need_wa = detect_harden_bp_fw();
- if (!need_wa)
- return false;
-
- __spectrev2_safe = false;
-
- /* forced off */
- if (__nospectre_v2 || cpu_mitigations_off()) {
- pr_info_once("spectrev2 mitigation disabled by command line option\n");
- __hardenbp_enab = false;
- return false;
- }
-
- if (need_wa < 0) {
- pr_warn_once("ARM_SMCCC_ARCH_WORKAROUND_1 missing from firmware\n");
- __hardenbp_enab = false;
- }
-
- return (need_wa > 0);
-}
-
-static void
-cpu_enable_branch_predictor_hardening(const struct arm64_cpu_capabilities *cap)
-{
- cap->matches(cap, SCOPE_LOCAL_CPU);
-}
-
static const __maybe_unused struct midr_range tx2_family_cpus[] = {
MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
@@ -876,11 +660,11 @@ const struct arm64_cpu_capabilities arm64_errata[] = {
},
#endif
{
- .desc = "Branch predictor hardening",
+ .desc = "Spectre-v2",
.capability = ARM64_SPECTRE_V2,
.type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM,
- .matches = check_branch_predictor,
- .cpu_enable = cpu_enable_branch_predictor_hardening,
+ .matches = has_spectre_v2,
+ .cpu_enable = spectre_v2_enable_mitigation,
},
#ifdef CONFIG_RANDOMIZE_BASE
{
@@ -949,20 +733,6 @@ const struct arm64_cpu_capabilities arm64_errata[] = {
}
};
-ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr,
- char *buf)
-{
- switch (get_spectre_v2_workaround_state()) {
- case ARM64_BP_HARDEN_NOT_REQUIRED:
- return sprintf(buf, "Not affected\n");
- case ARM64_BP_HARDEN_WA_NEEDED:
- return sprintf(buf, "Mitigation: Branch predictor hardening\n");
- case ARM64_BP_HARDEN_UNKNOWN:
- default:
- return sprintf(buf, "Vulnerable\n");
- }
-}
-
ssize_t cpu_show_spec_store_bypass(struct device *dev,
struct device_attribute *attr, char *buf)
{
diff --git a/arch/arm64/kernel/proton-pack.c b/arch/arm64/kernel/proton-pack.c
index c37bf468e4a4..4f1411b45301 100644
--- a/arch/arm64/kernel/proton-pack.c
+++ b/arch/arm64/kernel/proton-pack.c
@@ -17,7 +17,33 @@
* Authors: Will Deacon <will@kernel.org> and Marc Zyngier <maz@kernel.org>
*/
+#include <linux/arm-smccc.h>
+#include <linux/cpu.h>
#include <linux/device.h>
+#include <linux/prctl.h>
+
+#include <asm/spectre.h>
+#include <asm/traps.h>
+
+/*
+ * We try to ensure that the mitigation state can never change as the result of
+ * onlining a late CPU.
+ */
+static void update_mitigation_state(enum mitigation_state *oldp,
+ enum mitigation_state new)
+{
+ enum mitigation_state state;
+
+ do {
+ state = READ_ONCE(*oldp);
+ if (new <= state)
+ break;
+
+ /* Userspace almost certainly can't deal with this. */
+ if (WARN_ON(system_capabilities_finalized()))
+ break;
+ } while (cmpxchg_relaxed(oldp, state, new) != state);
+}
/*
* Spectre v1.
@@ -30,3 +56,265 @@ ssize_t cpu_show_spectre_v1(struct device *dev, struct device_attribute *attr,
{
return sprintf(buf, "Mitigation: __user pointer sanitization\n");
}
+
+/*
+ * Spectre v2.
+ *
+ * This one sucks. A CPU is either:
+ *
+ * - Mitigated in hardware and advertised by ID_AA64PFR0_EL1.CSV2.
+ * - Mitigated in hardware and listed in our "safe list".
+ * - Mitigated in software by firmware.
+ * - Mitigated in software by a CPU-specific dance in the kernel.
+ * - Vulnerable.
+ *
+ * It's not unlikely for different CPUs in a big.LITTLE system to fall into
+ * different camps.
+ */
+static enum mitigation_state spectre_v2_state;
+
+static bool __read_mostly __nospectre_v2;
+static int __init parse_spectre_v2_param(char *str)
+{
+ __nospectre_v2 = true;
+ return 0;
+}
+early_param("nospectre_v2", parse_spectre_v2_param);
+
+static bool spectre_v2_mitigations_off(void)
+{
+ bool ret = __nospectre_v2 || cpu_mitigations_off();
+
+ if (ret)
+ pr_info_once("spectre-v2 mitigation disabled by command line option\n");
+
+ return ret;
+}
+
+ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ switch (spectre_v2_state) {
+ case SPECTRE_UNAFFECTED:
+ return sprintf(buf, "Not affected\n");
+ case SPECTRE_MITIGATED:
+ return sprintf(buf, "Mitigation: Branch predictor hardening\n");
+ case SPECTRE_VULNERABLE:
+ fallthrough;
+ default:
+ return sprintf(buf, "Vulnerable\n");
+ }
+}
+
+static enum mitigation_state spectre_v2_get_cpu_hw_mitigation_state(void)
+{
+ u64 pfr0;
+ static const struct midr_range spectre_v2_safe_list[] = {
+ MIDR_ALL_VERSIONS(MIDR_CORTEX_A35),
+ MIDR_ALL_VERSIONS(MIDR_CORTEX_A53),
+ MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
+ MIDR_ALL_VERSIONS(MIDR_BRAHMA_B53),
+ MIDR_ALL_VERSIONS(MIDR_HISI_TSV110),
+ MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_3XX_SILVER),
+ MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER),
+ { /* sentinel */ }
+ };
+
+ /* If the CPU has CSV2 set, we're safe */
+ pfr0 = read_cpuid(ID_AA64PFR0_EL1);
+ if (cpuid_feature_extract_unsigned_field(pfr0, ID_AA64PFR0_CSV2_SHIFT))
+ return SPECTRE_UNAFFECTED;
+
+ /* Alternatively, we have a list of unaffected CPUs */
+ if (is_midr_in_range_list(read_cpuid_id(), spectre_v2_safe_list))
+ return SPECTRE_UNAFFECTED;
+
+ return SPECTRE_VULNERABLE;
+}
+
+#define SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED (1)
+
+static enum mitigation_state spectre_v2_get_cpu_fw_mitigation_state(void)
+{
+ int ret;
+ struct arm_smccc_res res;
+
+ arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
+ ARM_SMCCC_ARCH_WORKAROUND_1, &res);
+
+ ret = res.a0;
+ switch (ret) {
+ case SMCCC_RET_SUCCESS:
+ return SPECTRE_MITIGATED;
+ case SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED:
+ return SPECTRE_UNAFFECTED;
+ default:
+ fallthrough;
+ case SMCCC_RET_NOT_SUPPORTED:
+ return SPECTRE_VULNERABLE;
+ }
+}
+
+bool has_spectre_v2(const struct arm64_cpu_capabilities *entry, int scope)
+{
+ WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible());
+
+ if (spectre_v2_get_cpu_hw_mitigation_state() == SPECTRE_UNAFFECTED)
+ return false;
+
+ if (spectre_v2_get_cpu_fw_mitigation_state() == SPECTRE_UNAFFECTED)
+ return false;
+
+ return true;
+}
+
+DEFINE_PER_CPU_READ_MOSTLY(struct bp_hardening_data, bp_hardening_data);
+
+enum mitigation_state arm64_get_spectre_v2_state(void)
+{
+ return spectre_v2_state;
+}
+
+#ifdef CONFIG_KVM
+#ifdef CONFIG_RANDOMIZE_BASE
+#include <asm/cacheflush.h>
+#include <asm/kvm_asm.h>
+
+atomic_t arm64_el2_vector_last_slot = ATOMIC_INIT(-1);
+
+static void __copy_hyp_vect_bpi(int slot, const char *hyp_vecs_start,
+ const char *hyp_vecs_end)
+{
+ void *dst = lm_alias(__bp_harden_hyp_vecs + slot * SZ_2K);
+ int i;
+
+ for (i = 0; i < SZ_2K; i += 0x80)
+ memcpy(dst + i, hyp_vecs_start, hyp_vecs_end - hyp_vecs_start);
+
+ __flush_icache_range((uintptr_t)dst, (uintptr_t)dst + SZ_2K);
+}
+
+static void install_bp_hardening_cb(bp_hardening_cb_t fn)
+{
+ static DEFINE_RAW_SPINLOCK(bp_lock);
+ int cpu, slot = -1;
+ const char *hyp_vecs_start = __smccc_workaround_1_smc;
+ const char *hyp_vecs_end = __smccc_workaround_1_smc +
+ __SMCCC_WORKAROUND_1_SMC_SZ;
+
+ /*
+ * detect_harden_bp_fw() passes NULL for the hyp_vecs start/end if
+ * we're a guest. Skip the hyp-vectors work.
+ */
+ if (!is_hyp_mode_available()) {
+ __this_cpu_write(bp_hardening_data.fn, fn);
+ return;
+ }
+
+ raw_spin_lock(&bp_lock);
+ for_each_possible_cpu(cpu) {
+ if (per_cpu(bp_hardening_data.fn, cpu) == fn) {
+ slot = per_cpu(bp_hardening_data.hyp_vectors_slot, cpu);
+ break;
+ }
+ }
+
+ if (slot == -1) {
+ slot = atomic_inc_return(&arm64_el2_vector_last_slot);
+ BUG_ON(slot >= BP_HARDEN_EL2_SLOTS);
+ __copy_hyp_vect_bpi(slot, hyp_vecs_start, hyp_vecs_end);
+ }
+
+ __this_cpu_write(bp_hardening_data.hyp_vectors_slot, slot);
+ __this_cpu_write(bp_hardening_data.fn, fn);
+ raw_spin_unlock(&bp_lock);
+}
+#else
+static void install_bp_hardening_cb(bp_hardening_cb_t fn)
+{
+ __this_cpu_write(bp_hardening_data.fn, fn);
+}
+#endif /* CONFIG_RANDOMIZE_BASE */
+#endif /* CONFIG_KVM */
+
+static void call_smc_arch_workaround_1(void)
+{
+ arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_1, NULL);
+}
+
+static void call_hvc_arch_workaround_1(void)
+{
+ arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_WORKAROUND_1, NULL);
+}
+
+static void qcom_link_stack_sanitisation(void)
+{
+ u64 tmp;
+
+ asm volatile("mov %0, x30 \n"
+ ".rept 16 \n"
+ "bl . + 4 \n"
+ ".endr \n"
+ "mov x30, %0 \n"
+ : "=&r" (tmp));
+}
+
+static enum mitigation_state spectre_v2_enable_fw_mitigation(void)
+{
+ bp_hardening_cb_t cb;
+ enum mitigation_state state;
+
+ state = spectre_v2_get_cpu_fw_mitigation_state();
+ if (state != SPECTRE_MITIGATED)
+ return state;
+
+ if (spectre_v2_mitigations_off())
+ return SPECTRE_VULNERABLE;
+
+ switch (arm_smccc_1_1_get_conduit()) {
+ case SMCCC_CONDUIT_HVC:
+ cb = call_hvc_arch_workaround_1;
+ break;
+
+ case SMCCC_CONDUIT_SMC:
+ cb = call_smc_arch_workaround_1;
+ break;
+
+ default:
+ return SPECTRE_VULNERABLE;
+ }
+
+ install_bp_hardening_cb(cb);
+ return SPECTRE_MITIGATED;
+}
+
+static enum mitigation_state spectre_v2_enable_sw_mitigation(void)
+{
+ u32 midr;
+
+ if (spectre_v2_mitigations_off())
+ return SPECTRE_VULNERABLE;
+
+ midr = read_cpuid_id();
+ if (((midr & MIDR_CPU_MODEL_MASK) != MIDR_QCOM_FALKOR) &&
+ ((midr & MIDR_CPU_MODEL_MASK) != MIDR_QCOM_FALKOR_V1))
+ return SPECTRE_VULNERABLE;
+
+ install_bp_hardening_cb(qcom_link_stack_sanitisation);
+ return SPECTRE_MITIGATED;
+}
+
+void spectre_v2_enable_mitigation(const struct arm64_cpu_capabilities *__unused)
+{
+ enum mitigation_state state;
+
+ WARN_ON(preemptible());
+
+ state = spectre_v2_get_cpu_hw_mitigation_state();
+ if (state == SPECTRE_VULNERABLE)
+ state = spectre_v2_enable_fw_mitigation();
+ if (state == SPECTRE_VULNERABLE)
+ state = spectre_v2_enable_sw_mitigation();
+
+ update_mitigation_state(&spectre_v2_state, state);
+}
diff --git a/arch/arm64/kvm/hypercalls.c b/arch/arm64/kvm/hypercalls.c
index 550dfa3e53cd..413d46b9bc07 100644
--- a/arch/arm64/kvm/hypercalls.c
+++ b/arch/arm64/kvm/hypercalls.c
@@ -24,13 +24,13 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu)
feature = smccc_get_arg1(vcpu);
switch (feature) {
case ARM_SMCCC_ARCH_WORKAROUND_1:
- switch (kvm_arm_harden_branch_predictor()) {
- case KVM_BP_HARDEN_UNKNOWN:
+ switch (arm64_get_spectre_v2_state()) {
+ case SPECTRE_VULNERABLE:
break;
- case KVM_BP_HARDEN_WA_NEEDED:
+ case SPECTRE_MITIGATED:
val = SMCCC_RET_SUCCESS;
break;
- case KVM_BP_HARDEN_NOT_REQUIRED:
+ case SPECTRE_UNAFFECTED:
val = SMCCC_RET_NOT_REQUIRED;
break;
}
diff --git a/arch/arm64/kvm/psci.c b/arch/arm64/kvm/psci.c
index 83415e96b589..fbdd6f3bea7f 100644
--- a/arch/arm64/kvm/psci.c
+++ b/arch/arm64/kvm/psci.c
@@ -425,12 +425,12 @@ static int get_kernel_wa_level(u64 regid)
{
switch (regid) {
case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1:
- switch (kvm_arm_harden_branch_predictor()) {
- case KVM_BP_HARDEN_UNKNOWN:
+ switch (arm64_get_spectre_v2_state()) {
+ case SPECTRE_VULNERABLE:
return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_NOT_AVAIL;
- case KVM_BP_HARDEN_WA_NEEDED:
+ case SPECTRE_MITIGATED:
return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_AVAIL;
- case KVM_BP_HARDEN_NOT_REQUIRED:
+ case SPECTRE_UNAFFECTED:
return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_NOT_REQUIRED;
}
return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_NOT_AVAIL;