From c98bd29917281a5023f71a3148f538ad2709c0f0 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Fri, 9 Aug 2019 14:22:41 +0100 Subject: arm64: errata: use arm_smccc_1_1_get_conduit() Now that we have arm_smccc_1_1_get_conduit(), we can hide the PSCI implementation details from the arm64 cpu errata code, so let's do so. As arm_smccc_1_1_get_conduit() implicitly checks that the SMCCC version is at least SMCCC_VERSION_1_1, we no longer need to check this explicitly where switch statements have a default case, e.g. in has_ssbd_mitigation(). There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland Cc: Lorenzo Pieralisi Cc: Will Deacon Cc: Marc Zyngier Cc: Suzuki K Poulose Signed-off-by: Catalin Marinas --- arch/arm64/kernel/cpu_errata.c | 37 ++++++++++++------------------------- 1 file changed, 12 insertions(+), 25 deletions(-) (limited to 'arch/arm64/kernel') diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c index f593f4cffc0d..9c0b011eee20 100644 --- a/arch/arm64/kernel/cpu_errata.c +++ b/arch/arm64/kernel/cpu_errata.c @@ -6,7 +6,6 @@ */ #include -#include #include #include #include @@ -166,9 +165,7 @@ static void install_bp_hardening_cb(bp_hardening_cb_t fn, } #endif /* CONFIG_KVM_INDIRECT_VECTORS */ -#include #include -#include static void call_smc_arch_workaround_1(void) { @@ -212,11 +209,8 @@ static int detect_harden_bp_fw(void) struct arm_smccc_res res; u32 midr = read_cpuid_id(); - if (psci_ops.smccc_version == SMCCC_VERSION_1_0) - return -1; - - switch (psci_ops.conduit) { - case PSCI_CONDUIT_HVC: + switch (arm_smccc_1_1_get_conduit()) { + case SMCCC_CONDUIT_HVC: arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, ARM_SMCCC_ARCH_WORKAROUND_1, &res); switch ((int)res.a0) { @@ -234,7 +228,7 @@ static int detect_harden_bp_fw(void) } break; - case PSCI_CONDUIT_SMC: + case SMCCC_CONDUIT_SMC: arm_smccc_1_1_smc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, ARM_SMCCC_ARCH_WORKAROUND_1, &res); switch ((int)res.a0) { @@ -308,11 +302,11 @@ void __init arm64_update_smccc_conduit(struct alt_instr *alt, BUG_ON(nr_inst != 1); - switch (psci_ops.conduit) { - case PSCI_CONDUIT_HVC: + switch (arm_smccc_1_1_get_conduit()) { + case SMCCC_CONDUIT_HVC: insn = aarch64_insn_get_hvc_value(); break; - case PSCI_CONDUIT_SMC: + case SMCCC_CONDUIT_SMC: insn = aarch64_insn_get_smc_value(); break; default: @@ -351,12 +345,12 @@ void arm64_set_ssbd_mitigation(bool state) return; } - switch (psci_ops.conduit) { - case PSCI_CONDUIT_HVC: + switch (arm_smccc_1_1_get_conduit()) { + case SMCCC_CONDUIT_HVC: arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_WORKAROUND_2, state, NULL); break; - case PSCI_CONDUIT_SMC: + case SMCCC_CONDUIT_SMC: arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2, state, NULL); break; @@ -390,20 +384,13 @@ static bool has_ssbd_mitigation(const struct arm64_cpu_capabilities *entry, goto out_printmsg; } - if (psci_ops.smccc_version == SMCCC_VERSION_1_0) { - ssbd_state = ARM64_SSBD_UNKNOWN; - if (!this_cpu_safe) - __ssb_safe = false; - return false; - } - - switch (psci_ops.conduit) { - case PSCI_CONDUIT_HVC: + switch (arm_smccc_1_1_get_conduit()) { + case SMCCC_CONDUIT_HVC: arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, ARM_SMCCC_ARCH_WORKAROUND_2, &res); break; - case PSCI_CONDUIT_SMC: + case SMCCC_CONDUIT_SMC: arm_smccc_1_1_smc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, ARM_SMCCC_ARCH_WORKAROUND_2, &res); break; -- cgit v1.2.3 From e6ea46511b1ae8c4491904c79411fcd29139af14 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Fri, 9 Aug 2019 14:22:44 +0100 Subject: firmware: arm_sdei: use common SMCCC_CONDUIT_* Now that we have common definitions for SMCCC conduits, move the SDEI code over to them, and remove the SDEI-specific definitions. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland Acked-by: Lorenzo Pieralisi Acked-by: James Morse Acked-by: Will Deacon Signed-off-by: Catalin Marinas --- arch/arm64/kernel/sdei.c | 3 ++- drivers/firmware/arm_sdei.c | 12 ++++++------ include/linux/arm_sdei.h | 6 ------ 3 files changed, 8 insertions(+), 13 deletions(-) (limited to 'arch/arm64/kernel') diff --git a/arch/arm64/kernel/sdei.c b/arch/arm64/kernel/sdei.c index ea94cf8f9dc6..d6259dac62b6 100644 --- a/arch/arm64/kernel/sdei.c +++ b/arch/arm64/kernel/sdei.c @@ -2,6 +2,7 @@ // Copyright (C) 2017 Arm Ltd. #define pr_fmt(fmt) "sdei: " fmt +#include #include #include #include @@ -161,7 +162,7 @@ unsigned long sdei_arch_get_entry_point(int conduit) return 0; } - sdei_exit_mode = (conduit == CONDUIT_HVC) ? SDEI_EXIT_HVC : SDEI_EXIT_SMC; + sdei_exit_mode = (conduit == SMCCC_CONDUIT_HVC) ? SDEI_EXIT_HVC : SDEI_EXIT_SMC; #ifdef CONFIG_UNMAP_KERNEL_AT_EL0 if (arm64_kernel_unmapped_at_el0()) { diff --git a/drivers/firmware/arm_sdei.c b/drivers/firmware/arm_sdei.c index 9cd70d1a5622..a479023fa036 100644 --- a/drivers/firmware/arm_sdei.c +++ b/drivers/firmware/arm_sdei.c @@ -967,29 +967,29 @@ static int sdei_get_conduit(struct platform_device *pdev) if (np) { if (of_property_read_string(np, "method", &method)) { pr_warn("missing \"method\" property\n"); - return CONDUIT_INVALID; + return SMCCC_CONDUIT_NONE; } if (!strcmp("hvc", method)) { sdei_firmware_call = &sdei_smccc_hvc; - return CONDUIT_HVC; + return SMCCC_CONDUIT_HVC; } else if (!strcmp("smc", method)) { sdei_firmware_call = &sdei_smccc_smc; - return CONDUIT_SMC; + return SMCCC_CONDUIT_SMC; } pr_warn("invalid \"method\" property: %s\n", method); } else if (IS_ENABLED(CONFIG_ACPI) && !acpi_disabled) { if (acpi_psci_use_hvc()) { sdei_firmware_call = &sdei_smccc_hvc; - return CONDUIT_HVC; + return SMCCC_CONDUIT_HVC; } else { sdei_firmware_call = &sdei_smccc_smc; - return CONDUIT_SMC; + return SMCCC_CONDUIT_SMC; } } - return CONDUIT_INVALID; + return SMCCC_CONDUIT_NONE; } static int sdei_probe(struct platform_device *pdev) diff --git a/include/linux/arm_sdei.h b/include/linux/arm_sdei.h index 3305ea7f9dc7..0a241c5c911d 100644 --- a/include/linux/arm_sdei.h +++ b/include/linux/arm_sdei.h @@ -5,12 +5,6 @@ #include -enum sdei_conduit_types { - CONDUIT_INVALID = 0, - CONDUIT_SMC, - CONDUIT_HVC, -}; - #include #ifdef CONFIG_ARM_SDE_INTERFACE -- cgit v1.2.3 From ce4d5ca2b9dd5d85944eb93c1bbf9eb11b7a907d Mon Sep 17 00:00:00 2001 From: Steven Price Date: Mon, 21 Oct 2019 16:28:22 +0100 Subject: arm/arm64: Make use of the SMCCC 1.1 wrapper Rather than directly choosing which function to use based on psci_ops.conduit, use the new arm_smccc_1_1 wrapper instead. In some cases we still need to do some operations based on the conduit, but the code duplication is removed. No functional change. Signed-off-by: Steven Price Signed-off-by: Marc Zyngier --- arch/arm/mm/proc-v7-bugs.c | 13 +++---- arch/arm64/kernel/cpu_errata.c | 81 +++++++++++++++--------------------------- 2 files changed, 34 insertions(+), 60 deletions(-) (limited to 'arch/arm64/kernel') diff --git a/arch/arm/mm/proc-v7-bugs.c b/arch/arm/mm/proc-v7-bugs.c index 54d87506d3b5..7c90b4c615a5 100644 --- a/arch/arm/mm/proc-v7-bugs.c +++ b/arch/arm/mm/proc-v7-bugs.c @@ -74,12 +74,13 @@ static void cpu_v7_spectre_init(void) case ARM_CPU_PART_CORTEX_A72: { struct arm_smccc_res res; + arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, + ARM_SMCCC_ARCH_WORKAROUND_1, &res); + if ((int)res.a0 != 0) + return; + switch (arm_smccc_1_1_get_conduit()) { case SMCCC_CONDUIT_HVC: - arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, - ARM_SMCCC_ARCH_WORKAROUND_1, &res); - if ((int)res.a0 != 0) - break; per_cpu(harden_branch_predictor_fn, cpu) = call_hvc_arch_workaround_1; cpu_do_switch_mm = cpu_v7_hvc_switch_mm; @@ -87,10 +88,6 @@ static void cpu_v7_spectre_init(void) break; case SMCCC_CONDUIT_SMC: - arm_smccc_1_1_smc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, - ARM_SMCCC_ARCH_WORKAROUND_1, &res); - if ((int)res.a0 != 0) - break; per_cpu(harden_branch_predictor_fn, cpu) = call_smc_arch_workaround_1; cpu_do_switch_mm = cpu_v7_smc_switch_mm; diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c index 9c0b011eee20..401246e095e7 100644 --- a/arch/arm64/kernel/cpu_errata.c +++ b/arch/arm64/kernel/cpu_errata.c @@ -209,40 +209,31 @@ static int detect_harden_bp_fw(void) 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: - arm_smccc_1_1_hvc(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: - cb = call_hvc_arch_workaround_1; - /* This is a guest, no need to patch KVM vectors */ - smccc_start = NULL; - smccc_end = NULL; - break; - default: - return -1; - } + cb = call_hvc_arch_workaround_1; + /* This is a guest, no need to patch KVM vectors */ + smccc_start = NULL; + smccc_end = NULL; break; case SMCCC_CONDUIT_SMC: - arm_smccc_1_1_smc(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: - cb = call_smc_arch_workaround_1; - smccc_start = __smccc_workaround_1_smc_start; - smccc_end = __smccc_workaround_1_smc_end; - break; - default: - return -1; - } + cb = call_smc_arch_workaround_1; + smccc_start = __smccc_workaround_1_smc_start; + smccc_end = __smccc_workaround_1_smc_end; break; default: @@ -332,6 +323,8 @@ void __init arm64_enable_wa2_handling(struct alt_instr *alt, 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; @@ -345,19 +338,10 @@ void arm64_set_ssbd_mitigation(bool state) return; } - switch (arm_smccc_1_1_get_conduit()) { - case SMCCC_CONDUIT_HVC: - arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_WORKAROUND_2, state, NULL); - break; - - case SMCCC_CONDUIT_SMC: - arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2, state, NULL); - break; + conduit = arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_WORKAROUND_2, state, + NULL); - default: - WARN_ON_ONCE(1); - break; - } + WARN_ON_ONCE(conduit == SMCCC_CONDUIT_NONE); } static bool has_ssbd_mitigation(const struct arm64_cpu_capabilities *entry, @@ -367,6 +351,7 @@ static bool has_ssbd_mitigation(const struct arm64_cpu_capabilities *entry, bool required = true; s32 val; bool this_cpu_safe = false; + int conduit; WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible()); @@ -384,18 +369,10 @@ static bool has_ssbd_mitigation(const struct arm64_cpu_capabilities *entry, goto out_printmsg; } - switch (arm_smccc_1_1_get_conduit()) { - case SMCCC_CONDUIT_HVC: - arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, - ARM_SMCCC_ARCH_WORKAROUND_2, &res); - break; + conduit = arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, + ARM_SMCCC_ARCH_WORKAROUND_2, &res); - case SMCCC_CONDUIT_SMC: - arm_smccc_1_1_smc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, - ARM_SMCCC_ARCH_WORKAROUND_2, &res); - break; - - default: + if (conduit == SMCCC_CONDUIT_NONE) { ssbd_state = ARM64_SSBD_UNKNOWN; if (!this_cpu_safe) __ssb_safe = false; -- cgit v1.2.3 From e0685fa228fdaf386f82ac0d64b2d6f3e0ddd588 Mon Sep 17 00:00:00 2001 From: Steven Price Date: Mon, 21 Oct 2019 16:28:23 +0100 Subject: arm64: Retrieve stolen time as paravirtualized guest Enable paravirtualization features when running under a hypervisor supporting the PV_TIME_ST hypercall. For each (v)CPU, we ask the hypervisor for the location of a shared page which the hypervisor will use to report stolen time to us. We set pv_time_ops to the stolen time function which simply reads the stolen value from the shared page for a VCPU. We guarantee single-copy atomicity using READ_ONCE which means we can also read the stolen time for another VCPU than the currently running one while it is potentially being updated by the hypervisor. Signed-off-by: Steven Price Signed-off-by: Marc Zyngier --- Documentation/admin-guide/kernel-parameters.txt | 6 +- arch/arm64/include/asm/paravirt.h | 9 +- arch/arm64/kernel/paravirt.c | 140 ++++++++++++++++++++++++ arch/arm64/kernel/time.c | 3 + include/linux/cpuhotplug.h | 1 + 5 files changed, 155 insertions(+), 4 deletions(-) (limited to 'arch/arm64/kernel') diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index a84a83f8881e..19f465530e86 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -3083,9 +3083,9 @@ [X86,PV_OPS] Disable paravirtualized VMware scheduler clock and use the default one. - no-steal-acc [X86,KVM] Disable paravirtualized steal time accounting. - steal time is computed, but won't influence scheduler - behaviour + no-steal-acc [X86,KVM,ARM64] Disable paravirtualized steal time + accounting. steal time is computed, but won't + influence scheduler behaviour nolapic [X86-32,APIC] Do not enable or use the local APIC. diff --git a/arch/arm64/include/asm/paravirt.h b/arch/arm64/include/asm/paravirt.h index 799d9dd6f7cc..cf3a0fd7c1a7 100644 --- a/arch/arm64/include/asm/paravirt.h +++ b/arch/arm64/include/asm/paravirt.h @@ -21,6 +21,13 @@ static inline u64 paravirt_steal_clock(int cpu) { return pv_ops.time.steal_clock(cpu); } -#endif + +int __init pv_time_init(void); + +#else + +#define pv_time_init() do {} while (0) + +#endif // CONFIG_PARAVIRT #endif diff --git a/arch/arm64/kernel/paravirt.c b/arch/arm64/kernel/paravirt.c index 4cfed91fe256..1ef702b0be2d 100644 --- a/arch/arm64/kernel/paravirt.c +++ b/arch/arm64/kernel/paravirt.c @@ -6,13 +6,153 @@ * Author: Stefano Stabellini */ +#define pr_fmt(fmt) "arm-pv: " fmt + +#include +#include #include +#include #include +#include +#include +#include +#include #include + #include +#include +#include struct static_key paravirt_steal_enabled; struct static_key paravirt_steal_rq_enabled; struct paravirt_patch_template pv_ops; EXPORT_SYMBOL_GPL(pv_ops); + +struct pv_time_stolen_time_region { + struct pvclock_vcpu_stolen_time *kaddr; +}; + +static DEFINE_PER_CPU(struct pv_time_stolen_time_region, stolen_time_region); + +static bool steal_acc = true; +static int __init parse_no_stealacc(char *arg) +{ + steal_acc = false; + return 0; +} + +early_param("no-steal-acc", parse_no_stealacc); + +/* return stolen time in ns by asking the hypervisor */ +static u64 pv_steal_clock(int cpu) +{ + struct pv_time_stolen_time_region *reg; + + reg = per_cpu_ptr(&stolen_time_region, cpu); + if (!reg->kaddr) { + pr_warn_once("stolen time enabled but not configured for cpu %d\n", + cpu); + return 0; + } + + return le64_to_cpu(READ_ONCE(reg->kaddr->stolen_time)); +} + +static int stolen_time_dying_cpu(unsigned int cpu) +{ + struct pv_time_stolen_time_region *reg; + + reg = this_cpu_ptr(&stolen_time_region); + if (!reg->kaddr) + return 0; + + memunmap(reg->kaddr); + memset(reg, 0, sizeof(*reg)); + + return 0; +} + +static int init_stolen_time_cpu(unsigned int cpu) +{ + struct pv_time_stolen_time_region *reg; + struct arm_smccc_res res; + + reg = this_cpu_ptr(&stolen_time_region); + + arm_smccc_1_1_invoke(ARM_SMCCC_HV_PV_TIME_ST, &res); + + if (res.a0 == SMCCC_RET_NOT_SUPPORTED) + return -EINVAL; + + reg->kaddr = memremap(res.a0, + sizeof(struct pvclock_vcpu_stolen_time), + MEMREMAP_WB); + + if (!reg->kaddr) { + pr_warn("Failed to map stolen time data structure\n"); + return -ENOMEM; + } + + if (le32_to_cpu(reg->kaddr->revision) != 0 || + le32_to_cpu(reg->kaddr->attributes) != 0) { + pr_warn_once("Unexpected revision or attributes in stolen time data\n"); + return -ENXIO; + } + + return 0; +} + +static int pv_time_init_stolen_time(void) +{ + int ret; + + ret = cpuhp_setup_state(CPUHP_AP_ARM_KVMPV_STARTING, + "hypervisor/arm/pvtime:starting", + init_stolen_time_cpu, stolen_time_dying_cpu); + if (ret < 0) + return ret; + return 0; +} + +static bool has_pv_steal_clock(void) +{ + struct arm_smccc_res res; + + /* To detect the presence of PV time support we require SMCCC 1.1+ */ + if (psci_ops.smccc_version < SMCCC_VERSION_1_1) + return false; + + arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, + ARM_SMCCC_HV_PV_TIME_FEATURES, &res); + + if (res.a0 != SMCCC_RET_SUCCESS) + return false; + + arm_smccc_1_1_invoke(ARM_SMCCC_HV_PV_TIME_FEATURES, + ARM_SMCCC_HV_PV_TIME_ST, &res); + + return (res.a0 == SMCCC_RET_SUCCESS); +} + +int __init pv_time_init(void) +{ + int ret; + + if (!has_pv_steal_clock()) + return 0; + + ret = pv_time_init_stolen_time(); + if (ret) + return ret; + + pv_ops.time.steal_clock = pv_steal_clock; + + static_key_slow_inc(¶virt_steal_enabled); + if (steal_acc) + static_key_slow_inc(¶virt_steal_rq_enabled); + + pr_info("using stolen time PV\n"); + + return 0; +} diff --git a/arch/arm64/kernel/time.c b/arch/arm64/kernel/time.c index 0b2946414dc9..73f06d4b3aae 100644 --- a/arch/arm64/kernel/time.c +++ b/arch/arm64/kernel/time.c @@ -30,6 +30,7 @@ #include #include +#include unsigned long profile_pc(struct pt_regs *regs) { @@ -65,4 +66,6 @@ void __init time_init(void) /* Calibrate the delay loop directly */ lpj_fine = arch_timer_rate / HZ; + + pv_time_init(); } diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 068793a619ca..89d75edb5750 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -136,6 +136,7 @@ enum cpuhp_state { /* Must be the last timer callback */ CPUHP_AP_DUMMY_TIMER_STARTING, CPUHP_AP_ARM_XEN_STARTING, + CPUHP_AP_ARM_KVMPV_STARTING, CPUHP_AP_ARM_CORESIGHT_STARTING, CPUHP_AP_ARM64_ISNDEP_STARTING, CPUHP_AP_SMPCFD_DYING, -- cgit v1.2.3