Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Will Deacon:
 "There's quite a lot of code here, but much of it is due to the
  addition of a new PMU driver as well as some arm64-specific selftests
  which is an area where we've traditionally been lagging a bit.

  In terms of exciting features, this includes support for the Memory
  Tagging Extension which narrowly missed 5.9, hopefully allowing
  userspace to run with use-after-free detection in production on CPUs
  that support it. Work is ongoing to integrate the feature with KASAN
  for 5.11.

  Another change that I'm excited about (assuming they get the hardware
  right) is preparing the ASID allocator for sharing the CPU page-table
  with the SMMU. Those changes will also come in via Joerg with the
  IOMMU pull.

  We do stray outside of our usual directories in a few places, mostly
  due to core changes required by MTE. Although much of this has been
  Acked, there were a couple of places where we unfortunately didn't get
  any review feedback.

  Other than that, we ran into a handful of minor conflicts in -next,
  but nothing that should post any issues.

  Summary:

   - Userspace support for the Memory Tagging Extension introduced by
     Armv8.5. Kernel support (via KASAN) is likely to follow in 5.11.

   - Selftests for MTE, Pointer Authentication and FPSIMD/SVE context
     switching.

   - Fix and subsequent rewrite of our Spectre mitigations, including
     the addition of support for PR_SPEC_DISABLE_NOEXEC.

   - Support for the Armv8.3 Pointer Authentication enhancements.

   - Support for ASID pinning, which is required when sharing
     page-tables with the SMMU.

   - MM updates, including treating flush_tlb_fix_spurious_fault() as a
     no-op.

   - Perf/PMU driver updates, including addition of the ARM CMN PMU
     driver and also support to handle CPU PMU IRQs as NMIs.

   - Allow prefetchable PCI BARs to be exposed to userspace using normal
     non-cacheable mappings.

   - Implementation of ARCH_STACKWALK for unwinding.

   - Improve reporting of unexpected kernel traps due to BPF JIT
     failure.

   - Improve robustness of user-visible HWCAP strings and their
     corresponding numerical constants.

   - Removal of TEXT_OFFSET.

   - Removal of some unused functions, parameters and prototypes.

   - Removal of MPIDR-based topology detection in favour of firmware
     description.

   - Cleanups to handling of SVE and FPSIMD register state in
     preparation for potential future optimisation of handling across
     syscalls.

   - Cleanups to the SDEI driver in preparation for support in KVM.

   - Miscellaneous cleanups and refactoring work"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (148 commits)
  Revert "arm64: initialize per-cpu offsets earlier"
  arm64: random: Remove no longer needed prototypes
  arm64: initialize per-cpu offsets earlier
  kselftest/arm64: Check mte tagged user address in kernel
  kselftest/arm64: Verify KSM page merge for MTE pages
  kselftest/arm64: Verify all different mmap MTE options
  kselftest/arm64: Check forked child mte memory accessibility
  kselftest/arm64: Verify mte tag inclusion via prctl
  kselftest/arm64: Add utilities and a test to validate mte memory
  perf: arm-cmn: Fix conversion specifiers for node type
  perf: arm-cmn: Fix unsigned comparison to less than zero
  arm64: dbm: Invalidate local TLB when setting TCR_EL1.HD
  arm64: mm: Make flush_tlb_fix_spurious_fault() a no-op
  arm64: Add support for PR_SPEC_DISABLE_NOEXEC prctl() option
  arm64: Pull in task_stack_page() to Spectre-v4 mitigation code
  KVM: arm64: Allow patching EL2 vectors even with KASLR is not enabled
  arm64: Get rid of arm64_ssbd_state
  KVM: arm64: Convert ARCH_WORKAROUND_2 to arm64_get_spectre_v4_state()
  KVM: arm64: Get rid of kvm_arm_have_ssbd()
  KVM: arm64: Simplify handling of ARCH_WORKAROUND_2
  ...

1 files changed, 8 insertions, 479 deletions

diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index 560ba69e13c1..24d75af344b1 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -106,365 +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_KVM_INDIRECT_VECTORS
-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,
-				    const char *hyp_vecs_start,
-				    const char *hyp_vecs_end)
-{
-	static DEFINE_RAW_SPINLOCK(bp_lock);
-	int cpu, slot = -1;
-
-	/*
-	 * detect_harden_bp_fw() passes NULL for the hyp_vecs start/end if
-	 * we're a guest. Skip the hyp-vectors work.
-	 */
-	if (!hyp_vecs_start) {
-		__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,
-				      const char *hyp_vecs_start,
-				      const char *hyp_vecs_end)
-{
-	__this_cpu_write(bp_hardening_data.fn, fn);
-}
-#endif	/* CONFIG_KVM_INDIRECT_VECTORS */
-
-#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;
-	void *smccc_start, *smccc_end;
-	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;
-		/* This is a guest, no need to patch KVM vectors */
-		smccc_start = NULL;
-		smccc_end = NULL;
-		break;
-
-#if IS_ENABLED(CONFIG_KVM)
-	case SMCCC_CONDUIT_SMC:
-		cb = call_smc_arch_workaround_1;
-		smccc_start = __smccc_workaround_1_smc;
-		smccc_end = __smccc_workaround_1_smc +
-			__SMCCC_WORKAROUND_1_SMC_SZ;
-		break;
-#endif
-
-	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;
-
-	if (IS_ENABLED(CONFIG_HARDEN_BRANCH_PREDICTOR))
-		install_bp_hardening_cb(cb, smccc_start, smccc_end);
-
-	return 1;
-}
-
-DEFINE_PER_CPU_READ_MOSTLY(u64, arm64_ssbd_callback_required);
-
-int ssbd_state __read_mostly = ARM64_SSBD_KERNEL;
-static bool __ssb_safe = true;
-
-static const struct ssbd_options {
-	const char	*str;
-	int		state;
-} ssbd_options[] = {
-	{ "force-on",	ARM64_SSBD_FORCE_ENABLE, },
-	{ "force-off",	ARM64_SSBD_FORCE_DISABLE, },
-	{ "kernel",	ARM64_SSBD_KERNEL, },
-};
-
-static int __init ssbd_cfg(char *buf)
-{
-	int i;
-
-	if (!buf || !buf[0])
-		return -EINVAL;
-
-	for (i = 0; i < ARRAY_SIZE(ssbd_options); i++) {
-		int len = strlen(ssbd_options[i].str);
-
-		if (strncmp(buf, ssbd_options[i].str, len))
-			continue;
-
-		ssbd_state = ssbd_options[i].state;
-		return 0;
-	}
-
-	return -EINVAL;
-}
-early_param("ssbd", ssbd_cfg);
-
-void __init arm64_update_smccc_conduit(struct alt_instr *alt,
-				       __le32 *origptr, __le32 *updptr,
-				       int nr_inst)
-{
-	u32 insn;
-
-	BUG_ON(nr_inst != 1);
-
-	switch (arm_smccc_1_1_get_conduit()) {
-	case SMCCC_CONDUIT_HVC:
-		insn = aarch64_insn_get_hvc_value();
-		break;
-	case SMCCC_CONDUIT_SMC:
-		insn = aarch64_insn_get_smc_value();
-		break;
-	default:
-		return;
-	}
-
-	*updptr = cpu_to_le32(insn);
-}
-
-void __init arm64_enable_wa2_handling(struct alt_instr *alt,
-				      __le32 *origptr, __le32 *updptr,
-				      int nr_inst)
-{
-	BUG_ON(nr_inst != 1);
-	/*
-	 * Only allow mitigation on EL1 entry/exit and guest
-	 * ARCH_WORKAROUND_2 handling if the SSBD state allows it to
-	 * be flipped.
-	 */
-	if (arm64_get_ssbd_state() == ARM64_SSBD_KERNEL)
-		*updptr = cpu_to_le32(aarch64_insn_gen_nop());
-}
-
-void arm64_set_ssbd_mitigation(bool state)
-{
-	int conduit;
-
-	if (!IS_ENABLED(CONFIG_ARM64_SSBD)) {
-		pr_info_once("SSBD disabled by kernel configuration\n");
-		return;
-	}
-
-	if (this_cpu_has_cap(ARM64_SSBS)) {
-		if (state)
-			asm volatile(SET_PSTATE_SSBS(0));
-		else
-			asm volatile(SET_PSTATE_SSBS(1));
-		return;
-	}
-
-	conduit = arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_WORKAROUND_2, state,
-				       NULL);
-
-	WARN_ON_ONCE(conduit == SMCCC_CONDUIT_NONE);
-}
-
-static bool has_ssbd_mitigation(const struct arm64_cpu_capabilities *entry,
-				    int scope)
-{
-	struct arm_smccc_res res;
-	bool required = true;
-	s32 val;
-	bool this_cpu_safe = false;
-	int conduit;
-
-	WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible());
-
-	if (cpu_mitigations_off())
-		ssbd_state = ARM64_SSBD_FORCE_DISABLE;
-
-	/* delay setting __ssb_safe until we get a firmware response */
-	if (is_midr_in_range_list(read_cpuid_id(), entry->midr_range_list))
-		this_cpu_safe = true;
-
-	if (this_cpu_has_cap(ARM64_SSBS)) {
-		if (!this_cpu_safe)
-			__ssb_safe = false;
-		required = false;
-		goto out_printmsg;
-	}
-
-	conduit = arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
-				       ARM_SMCCC_ARCH_WORKAROUND_2, &res);
-
-	if (conduit == SMCCC_CONDUIT_NONE) {
-		ssbd_state = ARM64_SSBD_UNKNOWN;
-		if (!this_cpu_safe)
-			__ssb_safe = false;
-		return false;
-	}
-
-	val = (s32)res.a0;
-
-	switch (val) {
-	case SMCCC_RET_NOT_SUPPORTED:
-		ssbd_state = ARM64_SSBD_UNKNOWN;
-		if (!this_cpu_safe)
-			__ssb_safe = false;
-		return false;
-
-	/* machines with mixed mitigation requirements must not return this */
-	case SMCCC_RET_NOT_REQUIRED:
-		pr_info_once("%s mitigation not required\n", entry->desc);
-		ssbd_state = ARM64_SSBD_MITIGATED;
-		return false;
-
-	case SMCCC_RET_SUCCESS:
-		__ssb_safe = false;
-		required = true;
-		break;
-
-	case 1:	/* Mitigation not required on this CPU */
-		required = false;
-		break;
-
-	default:
-		WARN_ON(1);
-		if (!this_cpu_safe)
-			__ssb_safe = false;
-		return false;
-	}
-
-	switch (ssbd_state) {
-	case ARM64_SSBD_FORCE_DISABLE:
-		arm64_set_ssbd_mitigation(false);
-		required = false;
-		break;
-
-	case ARM64_SSBD_KERNEL:
-		if (required) {
-			__this_cpu_write(arm64_ssbd_callback_required, 1);
-			arm64_set_ssbd_mitigation(true);
-		}
-		break;
-
-	case ARM64_SSBD_FORCE_ENABLE:
-		arm64_set_ssbd_mitigation(true);
-		required = true;
-		break;
-
-	default:
-		WARN_ON(1);
-		break;
-	}
-
-out_printmsg:
-	switch (ssbd_state) {
-	case ARM64_SSBD_FORCE_DISABLE:
-		pr_info_once("%s disabled from command-line\n", entry->desc);
-		break;
-
-	case ARM64_SSBD_FORCE_ENABLE:
-		pr_info_once("%s forced from command-line\n", entry->desc);
-		break;
-	}
-
-	return required;
-}
-
-/* known invulnerable cores */
-static const struct midr_range arm64_ssb_cpus[] = {
-	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_QCOM_KRYO_3XX_SILVER),
-	MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER),
-	{},
-};
-
 #ifdef CONFIG_ARM64_ERRATUM_1463225
 DEFINE_PER_CPU(int, __in_cortex_a76_erratum_1463225_wa);
 
@@ -519,83 +160,6 @@ 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;
-
-	if (!IS_ENABLED(CONFIG_HARDEN_BRANCH_PREDICTOR)) {
-		pr_warn_once("spectrev2 mitigation disabled by kernel configuration\n");
-		__hardenbp_enab = false;
-		return 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 const __maybe_unused struct midr_range tx2_family_cpus[] = {
 	MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
 	MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
@@ -887,9 +451,11 @@ const struct arm64_cpu_capabilities arm64_errata[] = {
 	},
 #endif
 	{
-		.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
+		.desc = "Spectre-v2",
+		.capability = ARM64_SPECTRE_V2,
 		.type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM,
-		.matches = check_branch_predictor,
+		.matches = has_spectre_v2,
+		.cpu_enable = spectre_v2_enable_mitigation,
 	},
 #ifdef CONFIG_RANDOMIZE_BASE
 	{
@@ -899,11 +465,11 @@ const struct arm64_cpu_capabilities arm64_errata[] = {
 	},
 #endif
 	{
-		.desc = "Speculative Store Bypass Disable",
-		.capability = ARM64_SSBD,
+		.desc = "Spectre-v4",
+		.capability = ARM64_SPECTRE_V4,
 		.type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM,
-		.matches = has_ssbd_mitigation,
-		.midr_range_list = arm64_ssb_cpus,
+		.matches = has_spectre_v4,
+		.cpu_enable = spectre_v4_enable_mitigation,
 	},
 #ifdef CONFIG_ARM64_ERRATUM_1418040
 	{
@@ -960,40 +526,3 @@ const struct arm64_cpu_capabilities arm64_errata[] = {
 	{
 	}
 };
-
-ssize_t cpu_show_spectre_v1(struct device *dev, struct device_attribute *attr,
-			    char *buf)
-{
-	return sprintf(buf, "Mitigation: __user pointer sanitization\n");
-}
-
-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)
-{
-	if (__ssb_safe)
-		return sprintf(buf, "Not affected\n");
-
-	switch (ssbd_state) {
-	case ARM64_SSBD_KERNEL:
-	case ARM64_SSBD_FORCE_ENABLE:
-		if (IS_ENABLED(CONFIG_ARM64_SSBD))
-			return sprintf(buf,
-			    "Mitigation: Speculative Store Bypass disabled via prctl\n");
-	}
-
-	return sprintf(buf, "Vulnerable\n");
-}