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') 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 6848253ddeae9fa44680bab6212599283f9d4ef2 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Fri, 9 Aug 2019 14:22:42 +0100 Subject: arm: spectre-v2: 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 arm spectre-v2 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. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland Cc: Marc Zyngier Cc: Russell King Signed-off-by: Catalin Marinas --- arch/arm/mm/proc-v7-bugs.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) (limited to 'arch') diff --git a/arch/arm/mm/proc-v7-bugs.c b/arch/arm/mm/proc-v7-bugs.c index 9a07916af8dd..54d87506d3b5 100644 --- a/arch/arm/mm/proc-v7-bugs.c +++ b/arch/arm/mm/proc-v7-bugs.c @@ -1,7 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 #include #include -#include #include #include @@ -75,11 +74,8 @@ static void cpu_v7_spectre_init(void) case ARM_CPU_PART_CORTEX_A72: { struct arm_smccc_res res; - if (psci_ops.smccc_version == SMCCC_VERSION_1_0) - break; - - 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); if ((int)res.a0 != 0) @@ -90,7 +86,7 @@ static void cpu_v7_spectre_init(void) spectre_v2_method = "hypervisor"; 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); if ((int)res.a0 != 0) -- 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 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'arch') 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()) { -- cgit v1.2.3 From c726200dd106d4c58a281eea7159b8ba28a4ab34 Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Fri, 11 Oct 2019 13:07:05 +0200 Subject: KVM: arm/arm64: Allow reporting non-ISV data aborts to userspace For a long time, if a guest accessed memory outside of a memslot using any of the load/store instructions in the architecture which doesn't supply decoding information in the ESR_EL2 (the ISV bit is not set), the kernel would print the following message and terminate the VM as a result of returning -ENOSYS to userspace: load/store instruction decoding not implemented The reason behind this message is that KVM assumes that all accesses outside a memslot is an MMIO access which should be handled by userspace, and we originally expected to eventually implement some sort of decoding of load/store instructions where the ISV bit was not set. However, it turns out that many of the instructions which don't provide decoding information on abort are not safe to use for MMIO accesses, and the remaining few that would potentially make sense to use on MMIO accesses, such as those with register writeback, are not used in practice. It also turns out that fetching an instruction from guest memory can be a pretty horrible affair, involving stopping all CPUs on SMP systems, handling multiple corner cases of address translation in software, and more. It doesn't appear likely that we'll ever implement this in the kernel. What is much more common is that a user has misconfigured his/her guest and is actually not accessing an MMIO region, but just hitting some random hole in the IPA space. In this scenario, the error message above is almost misleading and has led to a great deal of confusion over the years. It is, nevertheless, ABI to userspace, and we therefore need to introduce a new capability that userspace explicitly enables to change behavior. This patch introduces KVM_CAP_ARM_NISV_TO_USER (NISV meaning Non-ISV) which does exactly that, and introduces a new exit reason to report the event to userspace. User space can then emulate an exception to the guest, restart the guest, suspend the guest, or take any other appropriate action as per the policy of the running system. Reported-by: Heinrich Schuchardt Signed-off-by: Christoffer Dall Reviewed-by: Alexander Graf Signed-off-by: Marc Zyngier --- arch/arm/include/asm/kvm_arm.h | 1 + arch/arm/include/asm/kvm_emulate.h | 5 +++++ arch/arm/include/asm/kvm_host.h | 8 ++++++++ arch/arm64/include/asm/kvm_emulate.h | 5 +++++ arch/arm64/include/asm/kvm_host.h | 8 ++++++++ 5 files changed, 27 insertions(+) (limited to 'arch') diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h index 0125aa059d5b..9c04bd810d07 100644 --- a/arch/arm/include/asm/kvm_arm.h +++ b/arch/arm/include/asm/kvm_arm.h @@ -162,6 +162,7 @@ #define HSR_ISV (_AC(1, UL) << HSR_ISV_SHIFT) #define HSR_SRT_SHIFT (16) #define HSR_SRT_MASK (0xf << HSR_SRT_SHIFT) +#define HSR_CM (1 << 8) #define HSR_FSC (0x3f) #define HSR_FSC_TYPE (0x3c) #define HSR_SSE (1 << 21) diff --git a/arch/arm/include/asm/kvm_emulate.h b/arch/arm/include/asm/kvm_emulate.h index 40002416efec..e8ef349c04b4 100644 --- a/arch/arm/include/asm/kvm_emulate.h +++ b/arch/arm/include/asm/kvm_emulate.h @@ -167,6 +167,11 @@ static inline bool kvm_vcpu_dabt_isvalid(struct kvm_vcpu *vcpu) return kvm_vcpu_get_hsr(vcpu) & HSR_ISV; } +static inline unsigned long kvm_vcpu_dabt_iss_nisv_sanitized(const struct kvm_vcpu *vcpu) +{ + return kvm_vcpu_get_hsr(vcpu) & (HSR_CM | HSR_WNR | HSR_FSC); +} + static inline bool kvm_vcpu_dabt_iswrite(struct kvm_vcpu *vcpu) { return kvm_vcpu_get_hsr(vcpu) & HSR_WNR; diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index 8a37c8e89777..19a92c49039c 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -76,6 +76,14 @@ struct kvm_arch { /* Mandated version of PSCI */ u32 psci_version; + + /* + * If we encounter a data abort without valid instruction syndrome + * information, report this to user space. User space can (and + * should) opt in to this feature if KVM_CAP_ARM_NISV_TO_USER is + * supported. + */ + bool return_nisv_io_abort_to_user; }; #define KVM_NR_MEM_OBJS 40 diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h index d69c1efc63e7..a3c967988e1d 100644 --- a/arch/arm64/include/asm/kvm_emulate.h +++ b/arch/arm64/include/asm/kvm_emulate.h @@ -258,6 +258,11 @@ static inline bool kvm_vcpu_dabt_isvalid(const struct kvm_vcpu *vcpu) return !!(kvm_vcpu_get_hsr(vcpu) & ESR_ELx_ISV); } +static inline unsigned long kvm_vcpu_dabt_iss_nisv_sanitized(const struct kvm_vcpu *vcpu) +{ + return kvm_vcpu_get_hsr(vcpu) & (ESR_ELx_CM | ESR_ELx_WNR | ESR_ELx_FSC); +} + static inline bool kvm_vcpu_dabt_issext(const struct kvm_vcpu *vcpu) { return !!(kvm_vcpu_get_hsr(vcpu) & ESR_ELx_SSE); diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index f656169db8c3..019bc560edc1 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -83,6 +83,14 @@ struct kvm_arch { /* Mandated version of PSCI */ u32 psci_version; + + /* + * If we encounter a data abort without valid instruction syndrome + * information, report this to user space. User space can (and + * should) opt in to this feature if KVM_CAP_ARM_NISV_TO_USER is + * supported. + */ + bool return_nisv_io_abort_to_user; }; #define KVM_NR_MEM_OBJS 40 -- cgit v1.2.3 From da345174ceca052469e4775e4ae263b5f27a9355 Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Fri, 11 Oct 2019 13:07:06 +0200 Subject: KVM: arm/arm64: Allow user injection of external data aborts In some scenarios, such as buggy guest or incorrect configuration of the VMM and firmware description data, userspace will detect a memory access to a portion of the IPA, which is not mapped to any MMIO region. For this purpose, the appropriate action is to inject an external abort to the guest. The kernel already has functionality to inject an external abort, but we need to wire up a signal from user space that lets user space tell the kernel to do this. It turns out, we already have the set event functionality which we can perfectly reuse for this. Signed-off-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm/include/uapi/asm/kvm.h | 3 ++- arch/arm/kvm/guest.c | 10 ++++++++++ arch/arm64/include/uapi/asm/kvm.h | 3 ++- arch/arm64/kvm/guest.c | 10 ++++++++++ arch/arm64/kvm/inject_fault.c | 4 ++-- 5 files changed, 26 insertions(+), 4 deletions(-) (limited to 'arch') diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h index 2769360f195c..03cd7c19a683 100644 --- a/arch/arm/include/uapi/asm/kvm.h +++ b/arch/arm/include/uapi/asm/kvm.h @@ -131,8 +131,9 @@ struct kvm_vcpu_events { struct { __u8 serror_pending; __u8 serror_has_esr; + __u8 ext_dabt_pending; /* Align it to 8 bytes */ - __u8 pad[6]; + __u8 pad[5]; __u64 serror_esr; } exception; __u32 reserved[12]; diff --git a/arch/arm/kvm/guest.c b/arch/arm/kvm/guest.c index 684cf64b4033..735f9b007e58 100644 --- a/arch/arm/kvm/guest.c +++ b/arch/arm/kvm/guest.c @@ -255,6 +255,12 @@ int __kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu, { events->exception.serror_pending = !!(*vcpu_hcr(vcpu) & HCR_VA); + /* + * We never return a pending ext_dabt here because we deliver it to + * the virtual CPU directly when setting the event and it's no longer + * 'pending' at this point. + */ + return 0; } @@ -263,12 +269,16 @@ int __kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu, { bool serror_pending = events->exception.serror_pending; bool has_esr = events->exception.serror_has_esr; + bool ext_dabt_pending = events->exception.ext_dabt_pending; if (serror_pending && has_esr) return -EINVAL; else if (serror_pending) kvm_inject_vabt(vcpu); + if (ext_dabt_pending) + kvm_inject_dabt(vcpu, kvm_vcpu_get_hfar(vcpu)); + return 0; } diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index 67c21f9bdbad..d49c17a80491 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -164,8 +164,9 @@ struct kvm_vcpu_events { struct { __u8 serror_pending; __u8 serror_has_esr; + __u8 ext_dabt_pending; /* Align it to 8 bytes */ - __u8 pad[6]; + __u8 pad[5]; __u64 serror_esr; } exception; __u32 reserved[12]; diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index dfd626447482..ca613a44c6ec 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -712,6 +712,12 @@ int __kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu, if (events->exception.serror_pending && events->exception.serror_has_esr) events->exception.serror_esr = vcpu_get_vsesr(vcpu); + /* + * We never return a pending ext_dabt here because we deliver it to + * the virtual CPU directly when setting the event and it's no longer + * 'pending' at this point. + */ + return 0; } @@ -720,6 +726,7 @@ int __kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu, { bool serror_pending = events->exception.serror_pending; bool has_esr = events->exception.serror_has_esr; + bool ext_dabt_pending = events->exception.ext_dabt_pending; if (serror_pending && has_esr) { if (!cpus_have_const_cap(ARM64_HAS_RAS_EXTN)) @@ -733,6 +740,9 @@ int __kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu, kvm_inject_vabt(vcpu); } + if (ext_dabt_pending) + kvm_inject_dabt(vcpu, kvm_vcpu_get_hfar(vcpu)); + return 0; } diff --git a/arch/arm64/kvm/inject_fault.c b/arch/arm64/kvm/inject_fault.c index a9d25a305af5..ccdb6a051ab2 100644 --- a/arch/arm64/kvm/inject_fault.c +++ b/arch/arm64/kvm/inject_fault.c @@ -109,7 +109,7 @@ static void inject_undef64(struct kvm_vcpu *vcpu) /** * kvm_inject_dabt - inject a data abort into the guest - * @vcpu: The VCPU to receive the undefined exception + * @vcpu: The VCPU to receive the data abort * @addr: The address to report in the DFAR * * It is assumed that this code is called from the VCPU thread and that the @@ -125,7 +125,7 @@ void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr) /** * kvm_inject_pabt - inject a prefetch abort into the guest - * @vcpu: The VCPU to receive the undefined exception + * @vcpu: The VCPU to receive the prefetch abort * @addr: The address to report in the DFAR * * It is assumed that this code is called from the VCPU thread and that the -- cgit v1.2.3 From 55009c6ed2d24fc0f5521ab2482f145d269389ea Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Mon, 21 Oct 2019 16:28:15 +0100 Subject: KVM: arm/arm64: Factor out hypercall handling from PSCI code We currently intertwine the KVM PSCI implementation with the general dispatch of hypercall handling, which makes perfect sense because PSCI is the only category of hypercalls we support. However, as we are about to support additional hypercalls, factor out this functionality into a separate hypercall handler file. Signed-off-by: Christoffer Dall [steven.price@arm.com: rebased] Reviewed-by: Andrew Jones Signed-off-by: Steven Price Signed-off-by: Marc Zyngier --- arch/arm/kvm/Makefile | 2 +- arch/arm/kvm/handle_exit.c | 2 +- arch/arm64/kvm/Makefile | 1 + arch/arm64/kvm/handle_exit.c | 4 ++-- 4 files changed, 5 insertions(+), 4 deletions(-) (limited to 'arch') diff --git a/arch/arm/kvm/Makefile b/arch/arm/kvm/Makefile index b76b75bd9e00..e442d82821df 100644 --- a/arch/arm/kvm/Makefile +++ b/arch/arm/kvm/Makefile @@ -24,7 +24,7 @@ obj-y += kvm-arm.o init.o interrupts.o obj-y += handle_exit.o guest.o emulate.o reset.o obj-y += coproc.o coproc_a15.o coproc_a7.o vgic-v3-coproc.o obj-y += $(KVM)/arm/arm.o $(KVM)/arm/mmu.o $(KVM)/arm/mmio.o -obj-y += $(KVM)/arm/psci.o $(KVM)/arm/perf.o +obj-y += $(KVM)/arm/psci.o $(KVM)/arm/perf.o $(KVM)/arm/hypercalls.o obj-y += $(KVM)/arm/aarch32.o obj-y += $(KVM)/arm/vgic/vgic.o diff --git a/arch/arm/kvm/handle_exit.c b/arch/arm/kvm/handle_exit.c index 2a6a1394d26e..e58a89d2f13f 100644 --- a/arch/arm/kvm/handle_exit.c +++ b/arch/arm/kvm/handle_exit.c @@ -9,7 +9,7 @@ #include #include #include -#include +#include #include #include "trace.h" diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile index 3ac1a64d2fb9..73dce4d47d47 100644 --- a/arch/arm64/kvm/Makefile +++ b/arch/arm64/kvm/Makefile @@ -13,6 +13,7 @@ obj-$(CONFIG_KVM_ARM_HOST) += hyp/ kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o $(KVM)/vfio.o kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/arm.o $(KVM)/arm/mmu.o $(KVM)/arm/mmio.o kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/psci.o $(KVM)/arm/perf.o +kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/hypercalls.o kvm-$(CONFIG_KVM_ARM_HOST) += inject_fault.o regmap.o va_layout.o kvm-$(CONFIG_KVM_ARM_HOST) += hyp.o hyp-init.o handle_exit.o diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index 706cca23f0d2..aacfc55de44c 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -11,8 +11,6 @@ #include #include -#include - #include #include #include @@ -22,6 +20,8 @@ #include #include +#include + #define CREATE_TRACE_POINTS #include "trace.h" -- cgit v1.2.3 From b48c1a45a190898103cec28771efc399fd65a05a Mon Sep 17 00:00:00 2001 From: Steven Price Date: Mon, 21 Oct 2019 16:28:16 +0100 Subject: KVM: arm64: Implement PV_TIME_FEATURES call This provides a mechanism for querying which paravirtualized time features are available in this hypervisor. Also add the header file which defines the ABI for the paravirtualized time features we're about to add. Signed-off-by: Steven Price Signed-off-by: Marc Zyngier --- arch/arm/include/asm/kvm_host.h | 6 ++++++ arch/arm64/include/asm/kvm_host.h | 2 ++ arch/arm64/include/asm/pvclock-abi.h | 17 +++++++++++++++++ arch/arm64/kvm/Makefile | 1 + 4 files changed, 26 insertions(+) create mode 100644 arch/arm64/include/asm/pvclock-abi.h (limited to 'arch') diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index 8a37c8e89777..5a0c3569ebde 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -7,6 +7,7 @@ #ifndef __ARM_KVM_HOST_H__ #define __ARM_KVM_HOST_H__ +#include #include #include #include @@ -323,6 +324,11 @@ static inline int kvm_arch_vm_ioctl_check_extension(struct kvm *kvm, long ext) int kvm_perf_init(void); int kvm_perf_teardown(void); +static inline long kvm_hypercall_pv_features(struct kvm_vcpu *vcpu) +{ + return SMCCC_RET_NOT_SUPPORTED; +} + void kvm_mmu_wp_memory_region(struct kvm *kvm, int slot); struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr); diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index f656169db8c3..93b46d9526d0 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -478,6 +478,8 @@ void handle_exit_early(struct kvm_vcpu *vcpu, struct kvm_run *run, int kvm_perf_init(void); int kvm_perf_teardown(void); +long kvm_hypercall_pv_features(struct kvm_vcpu *vcpu); + void kvm_set_sei_esr(struct kvm_vcpu *vcpu, u64 syndrome); struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr); diff --git a/arch/arm64/include/asm/pvclock-abi.h b/arch/arm64/include/asm/pvclock-abi.h new file mode 100644 index 000000000000..c4f1c0a0789c --- /dev/null +++ b/arch/arm64/include/asm/pvclock-abi.h @@ -0,0 +1,17 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright (C) 2019 Arm Ltd. */ + +#ifndef __ASM_PVCLOCK_ABI_H +#define __ASM_PVCLOCK_ABI_H + +/* The below structure is defined in ARM DEN0057A */ + +struct pvclock_vcpu_stolen_time { + __le32 revision; + __le32 attributes; + __le64 stolen_time; + /* Structure must be 64 byte aligned, pad to that size */ + u8 padding[48]; +} __packed; + +#endif diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile index 73dce4d47d47..5ffbdc39e780 100644 --- a/arch/arm64/kvm/Makefile +++ b/arch/arm64/kvm/Makefile @@ -14,6 +14,7 @@ kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/e kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/arm.o $(KVM)/arm/mmu.o $(KVM)/arm/mmio.o kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/psci.o $(KVM)/arm/perf.o kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/hypercalls.o +kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/pvtime.o kvm-$(CONFIG_KVM_ARM_HOST) += inject_fault.o regmap.o va_layout.o kvm-$(CONFIG_KVM_ARM_HOST) += hyp.o hyp-init.o handle_exit.o -- cgit v1.2.3 From 8564d6372a7d8a6d440441b8ed8020f97f744450 Mon Sep 17 00:00:00 2001 From: Steven Price Date: Mon, 21 Oct 2019 16:28:18 +0100 Subject: KVM: arm64: Support stolen time reporting via shared structure Implement the service call for configuring a shared structure between a VCPU and the hypervisor in which the hypervisor can write the time stolen from the VCPU's execution time by other tasks on the host. User space allocates memory which is placed at an IPA also chosen by user space. The hypervisor then updates the shared structure using kvm_put_guest() to ensure single copy atomicity of the 64-bit value reporting the stolen time in nanoseconds. Whenever stolen time is enabled by the guest, the stolen time counter is reset. The stolen time itself is retrieved from the sched_info structure maintained by the Linux scheduler code. We enable SCHEDSTATS when selecting KVM Kconfig to ensure this value is meaningful. Signed-off-by: Steven Price Signed-off-by: Marc Zyngier --- arch/arm/include/asm/kvm_host.h | 19 +++++++++++++++++++ arch/arm64/include/asm/kvm_host.h | 20 ++++++++++++++++++++ arch/arm64/kvm/Kconfig | 1 + 3 files changed, 40 insertions(+) (limited to 'arch') diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index 5a0c3569ebde..5a077f85813f 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -39,6 +39,7 @@ KVM_ARCH_REQ_FLAGS(0, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP) #define KVM_REQ_IRQ_PENDING KVM_ARCH_REQ(1) #define KVM_REQ_VCPU_RESET KVM_ARCH_REQ(2) +#define KVM_REQ_RECORD_STEAL KVM_ARCH_REQ(3) DECLARE_STATIC_KEY_FALSE(userspace_irqchip_in_use); @@ -329,6 +330,24 @@ static inline long kvm_hypercall_pv_features(struct kvm_vcpu *vcpu) return SMCCC_RET_NOT_SUPPORTED; } +static inline gpa_t kvm_init_stolen_time(struct kvm_vcpu *vcpu) +{ + return GPA_INVALID; +} + +static inline void kvm_update_stolen_time(struct kvm_vcpu *vcpu) +{ +} + +static inline void kvm_arm_pvtime_vcpu_init(struct kvm_vcpu_arch *vcpu_arch) +{ +} + +static inline bool kvm_arm_is_pvtime_enabled(struct kvm_vcpu_arch *vcpu_arch) +{ + return false; +} + void kvm_mmu_wp_memory_region(struct kvm *kvm, int slot); struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr); diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 93b46d9526d0..75ef37f79633 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -44,6 +44,7 @@ KVM_ARCH_REQ_FLAGS(0, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP) #define KVM_REQ_IRQ_PENDING KVM_ARCH_REQ(1) #define KVM_REQ_VCPU_RESET KVM_ARCH_REQ(2) +#define KVM_REQ_RECORD_STEAL KVM_ARCH_REQ(3) DECLARE_STATIC_KEY_FALSE(userspace_irqchip_in_use); @@ -338,6 +339,13 @@ struct kvm_vcpu_arch { /* True when deferrable sysregs are loaded on the physical CPU, * see kvm_vcpu_load_sysregs and kvm_vcpu_put_sysregs. */ bool sysregs_loaded_on_cpu; + + /* Guest PV state */ + struct { + u64 steal; + u64 last_steal; + gpa_t base; + } steal; }; /* Pointer to the vcpu's SVE FFR for sve_{save,load}_state() */ @@ -479,6 +487,18 @@ int kvm_perf_init(void); int kvm_perf_teardown(void); long kvm_hypercall_pv_features(struct kvm_vcpu *vcpu); +gpa_t kvm_init_stolen_time(struct kvm_vcpu *vcpu); +void kvm_update_stolen_time(struct kvm_vcpu *vcpu); + +static inline void kvm_arm_pvtime_vcpu_init(struct kvm_vcpu_arch *vcpu_arch) +{ + vcpu_arch->steal.base = GPA_INVALID; +} + +static inline bool kvm_arm_is_pvtime_enabled(struct kvm_vcpu_arch *vcpu_arch) +{ + return (vcpu_arch->steal.base != GPA_INVALID); +} void kvm_set_sei_esr(struct kvm_vcpu *vcpu, u64 syndrome); diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig index a67121d419a2..d8b88e40d223 100644 --- a/arch/arm64/kvm/Kconfig +++ b/arch/arm64/kvm/Kconfig @@ -39,6 +39,7 @@ config KVM select IRQ_BYPASS_MANAGER select HAVE_KVM_IRQ_BYPASS select HAVE_KVM_VCPU_RUN_PID_CHANGE + select SCHEDSTATS ---help--- Support hosting virtualized guest machines. We don't support KVM with 16K page tables yet, due to the multiple -- cgit v1.2.3 From 58772e9a3db72d032eeb12bc011bc5184a3925f4 Mon Sep 17 00:00:00 2001 From: Steven Price Date: Mon, 21 Oct 2019 16:28:20 +0100 Subject: KVM: arm64: Provide VCPU attributes for stolen time Allow user space to inform the KVM host where in the physical memory map the paravirtualized time structures should be located. User space can set an attribute on the VCPU providing the IPA base address of the stolen time structure for that VCPU. This must be repeated for every VCPU in the VM. The address is given in terms of the physical address visible to the guest and must be 64 byte aligned. The guest will discover the address via a hypercall. Signed-off-by: Steven Price Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/kvm_host.h | 7 +++++++ arch/arm64/include/uapi/asm/kvm.h | 2 ++ arch/arm64/kvm/guest.c | 9 +++++++++ 3 files changed, 18 insertions(+) (limited to 'arch') diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 75ef37f79633..eb1f33af45aa 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -490,6 +490,13 @@ long kvm_hypercall_pv_features(struct kvm_vcpu *vcpu); gpa_t kvm_init_stolen_time(struct kvm_vcpu *vcpu); void kvm_update_stolen_time(struct kvm_vcpu *vcpu); +int kvm_arm_pvtime_set_attr(struct kvm_vcpu *vcpu, + struct kvm_device_attr *attr); +int kvm_arm_pvtime_get_attr(struct kvm_vcpu *vcpu, + struct kvm_device_attr *attr); +int kvm_arm_pvtime_has_attr(struct kvm_vcpu *vcpu, + struct kvm_device_attr *attr); + static inline void kvm_arm_pvtime_vcpu_init(struct kvm_vcpu_arch *vcpu_arch) { vcpu_arch->steal.base = GPA_INVALID; diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index 67c21f9bdbad..cff1ba12c768 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -323,6 +323,8 @@ struct kvm_vcpu_events { #define KVM_ARM_VCPU_TIMER_CTRL 1 #define KVM_ARM_VCPU_TIMER_IRQ_VTIMER 0 #define KVM_ARM_VCPU_TIMER_IRQ_PTIMER 1 +#define KVM_ARM_VCPU_PVTIME_CTRL 2 +#define KVM_ARM_VCPU_PVTIME_IPA 0 /* KVM_IRQ_LINE irq field index values */ #define KVM_ARM_IRQ_VCPU2_SHIFT 28 diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index dfd626447482..d3ac9d2fd405 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -858,6 +858,9 @@ int kvm_arm_vcpu_arch_set_attr(struct kvm_vcpu *vcpu, case KVM_ARM_VCPU_TIMER_CTRL: ret = kvm_arm_timer_set_attr(vcpu, attr); break; + case KVM_ARM_VCPU_PVTIME_CTRL: + ret = kvm_arm_pvtime_set_attr(vcpu, attr); + break; default: ret = -ENXIO; break; @@ -878,6 +881,9 @@ int kvm_arm_vcpu_arch_get_attr(struct kvm_vcpu *vcpu, case KVM_ARM_VCPU_TIMER_CTRL: ret = kvm_arm_timer_get_attr(vcpu, attr); break; + case KVM_ARM_VCPU_PVTIME_CTRL: + ret = kvm_arm_pvtime_get_attr(vcpu, attr); + break; default: ret = -ENXIO; break; @@ -898,6 +904,9 @@ int kvm_arm_vcpu_arch_has_attr(struct kvm_vcpu *vcpu, case KVM_ARM_VCPU_TIMER_CTRL: ret = kvm_arm_timer_has_attr(vcpu, attr); break; + case KVM_ARM_VCPU_PVTIME_CTRL: + ret = kvm_arm_pvtime_has_attr(vcpu, attr); + break; default: ret = -ENXIO; break; -- 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') 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 --- arch/arm64/include/asm/paravirt.h | 9 ++- arch/arm64/kernel/paravirt.c | 140 ++++++++++++++++++++++++++++++++++++++ arch/arm64/kernel/time.c | 3 + 3 files changed, 151 insertions(+), 1 deletion(-) (limited to 'arch') 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(); } -- cgit v1.2.3 From c7892db5dd6afe921ead502aff7440a1e450d947 Mon Sep 17 00:00:00 2001 From: Steven Price Date: Thu, 24 Oct 2019 14:31:11 +0100 Subject: KVM: arm64: Select TASK_DELAY_ACCT+TASKSTATS rather than SCHEDSTATS SCHEDSTATS requires DEBUG_KERNEL (and PROC_FS) and therefore isn't a good choice for enabling the scheduling statistics required for stolen time. Instead match the x86 configuration and select TASK_DELAY_ACCT and TASKSTATS. This adds the dependencies of NET && MULTIUSER for arm64 KVM. Suggested-by: Marc Zyngier Fixes: 8564d6372a7d ("KVM: arm64: Support stolen time reporting via shared structure") Signed-off-by: Steven Price Signed-off-by: Marc Zyngier --- arch/arm64/kvm/Kconfig | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig index d8b88e40d223..a475c68cbfec 100644 --- a/arch/arm64/kvm/Kconfig +++ b/arch/arm64/kvm/Kconfig @@ -21,6 +21,8 @@ if VIRTUALIZATION config KVM bool "Kernel-based Virtual Machine (KVM) support" depends on OF + # for TASKSTATS/TASK_DELAY_ACCT: + depends on NET && MULTIUSER select MMU_NOTIFIER select PREEMPT_NOTIFIERS select HAVE_KVM_CPU_RELAX_INTERCEPT @@ -39,7 +41,8 @@ config KVM select IRQ_BYPASS_MANAGER select HAVE_KVM_IRQ_BYPASS select HAVE_KVM_VCPU_RUN_PID_CHANGE - select SCHEDSTATS + select TASKSTATS + select TASK_DELAY_ACCT ---help--- Support hosting virtualized guest machines. We don't support KVM with 16K page tables yet, due to the multiple -- cgit v1.2.3 From 01d035d796fec0ab23dc3f3a3a9f58bbe034fc5b Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Sun, 27 Oct 2019 09:19:50 +0100 Subject: KVM: arm/arm64: Show halt poll counters in debugfs ARM/ARM64 has counters halt_successful_poll, halt_attempted_poll, halt_poll_invalid, and halt_wakeup but never exposed those in debugfs. Signed-off-by: Christian Borntraeger Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/1572164390-5851-1-git-send-email-borntraeger@de.ibm.com --- arch/arm/kvm/guest.c | 4 ++++ arch/arm64/kvm/guest.c | 4 ++++ 2 files changed, 8 insertions(+) (limited to 'arch') diff --git a/arch/arm/kvm/guest.c b/arch/arm/kvm/guest.c index 684cf64b4033..66964642cd42 100644 --- a/arch/arm/kvm/guest.c +++ b/arch/arm/kvm/guest.c @@ -21,6 +21,10 @@ #define VCPU_STAT(x) { #x, offsetof(struct kvm_vcpu, stat.x), KVM_STAT_VCPU } struct kvm_stats_debugfs_item debugfs_entries[] = { + VCPU_STAT(halt_successful_poll), + VCPU_STAT(halt_attempted_poll), + VCPU_STAT(halt_poll_invalid), + VCPU_STAT(halt_wakeup), VCPU_STAT(hvc_exit_stat), VCPU_STAT(wfe_exit_stat), VCPU_STAT(wfi_exit_stat), diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index dfd626447482..260ea3158682 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -34,6 +34,10 @@ #define VCPU_STAT(x) { #x, offsetof(struct kvm_vcpu, stat.x), KVM_STAT_VCPU } struct kvm_stats_debugfs_item debugfs_entries[] = { + VCPU_STAT(halt_successful_poll), + VCPU_STAT(halt_attempted_poll), + VCPU_STAT(halt_poll_invalid), + VCPU_STAT(halt_wakeup), VCPU_STAT(hvc_exit_stat), VCPU_STAT(wfe_exit_stat), VCPU_STAT(wfi_exit_stat), -- cgit v1.2.3 From 5c401308017f256ae9de804b4a1c65be1d390571 Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Mon, 28 Oct 2019 14:05:41 +0100 Subject: KVM: arm64: Don't set HCR_EL2.TVM when S2FWB is supported On CPUs that support S2FWB (Armv8.4+), KVM configures the stage 2 page tables to override the memory attributes of memory accesses, regardless of the stage 1 page table configurations, and also when the stage 1 MMU is turned off. This results in all memory accesses to RAM being cacheable, including during early boot of the guest. On CPUs without this feature, memory accesses were non-cacheable during boot until the guest turned on the stage 1 MMU, and we had to detect when the guest turned on the MMU, such that we could invalidate all cache entries and ensure a consistent view of memory with the MMU turned on. When the guest turned on the caches, we would call stage2_flush_vm() from kvm_toggle_cache(). However, stage2_flush_vm() walks all the stage 2 tables, and calls __kvm_flush-dcache_pte, which on a system with S2FWB does ... absolutely nothing. We can avoid that whole song and dance, and simply not set TVM when creating a VM on a system that has S2FWB. Signed-off-by: Christoffer Dall Signed-off-by: Marc Zyngier Reviewed-by: Mark Rutland Link: https://lore.kernel.org/r/20191028130541.30536-1-christoffer.dall@arm.com --- arch/arm64/include/asm/kvm_arm.h | 3 +-- arch/arm64/include/asm/kvm_emulate.h | 12 +++++++++++- 2 files changed, 12 insertions(+), 3 deletions(-) (limited to 'arch') diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h index ddf9d762ac62..6e5d839f42b5 100644 --- a/arch/arm64/include/asm/kvm_arm.h +++ b/arch/arm64/include/asm/kvm_arm.h @@ -61,7 +61,6 @@ * RW: 64bit by default, can be overridden for 32bit VMs * TAC: Trap ACTLR * TSC: Trap SMC - * TVM: Trap VM ops (until M+C set in SCTLR_EL1) * TSW: Trap cache operations by set/way * TWE: Trap WFE * TWI: Trap WFI @@ -74,7 +73,7 @@ * SWIO: Turn set/way invalidates into set/way clean+invalidate */ #define HCR_GUEST_FLAGS (HCR_TSC | HCR_TSW | HCR_TWE | HCR_TWI | HCR_VM | \ - HCR_TVM | HCR_BSU_IS | HCR_FB | HCR_TAC | \ + HCR_BSU_IS | HCR_FB | HCR_TAC | \ HCR_AMO | HCR_SWIO | HCR_TIDCP | HCR_RW | HCR_TLOR | \ HCR_FMO | HCR_IMO) #define HCR_VIRT_EXCP_MASK (HCR_VSE | HCR_VI | HCR_VF) diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h index d69c1efc63e7..6e92f6c7b1e4 100644 --- a/arch/arm64/include/asm/kvm_emulate.h +++ b/arch/arm64/include/asm/kvm_emulate.h @@ -53,8 +53,18 @@ static inline void vcpu_reset_hcr(struct kvm_vcpu *vcpu) /* trap error record accesses */ vcpu->arch.hcr_el2 |= HCR_TERR; } - if (cpus_have_const_cap(ARM64_HAS_STAGE2_FWB)) + + if (cpus_have_const_cap(ARM64_HAS_STAGE2_FWB)) { vcpu->arch.hcr_el2 |= HCR_FWB; + } else { + /* + * For non-FWB CPUs, we trap VM ops (HCR_EL2.TVM) until M+C + * get set in SCTLR_EL1 such that we can detect when the guest + * MMU gets turned on and do the necessary cache maintenance + * then. + */ + vcpu->arch.hcr_el2 |= HCR_TVM; + } if (test_bit(KVM_ARM_VCPU_EL1_32BIT, vcpu->arch.features)) vcpu->arch.hcr_el2 &= ~HCR_RW; -- cgit v1.2.3 From ef2e78ddadbb939ce79553b10dee0131d65d8f3e Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Thu, 7 Nov 2019 16:04:12 +0000 Subject: KVM: arm64: Opportunistically turn off WFI trapping when using direct LPI injection Just like we do for WFE trapping, it can be useful to turn off WFI trapping when the physical CPU is not oversubscribed (that is, the vcpu is the only runnable process on this CPU) *and* that we're using direct injection of interrupts. The conditions are reevaluated on each vcpu_load(), ensuring that we don't switch to this mode on a busy system. On a GICv4 system, this has the effect of reducing the generation of doorbell interrupts to zero when the right conditions are met, which is a huge improvement over the current situation (where the doorbells are screaming if the CPU ever hits a blocking WFI). Signed-off-by: Marc Zyngier Reviewed-by: Zenghui Yu Reviewed-by: Christoffer Dall Link: https://lore.kernel.org/r/20191107160412.30301-3-maz@kernel.org --- arch/arm/include/asm/kvm_emulate.h | 4 ++-- arch/arm64/include/asm/kvm_emulate.h | 9 +++++++-- 2 files changed, 9 insertions(+), 4 deletions(-) (limited to 'arch') diff --git a/arch/arm/include/asm/kvm_emulate.h b/arch/arm/include/asm/kvm_emulate.h index 40002416efec..023c01cad2b1 100644 --- a/arch/arm/include/asm/kvm_emulate.h +++ b/arch/arm/include/asm/kvm_emulate.h @@ -95,12 +95,12 @@ static inline unsigned long *vcpu_hcr(const struct kvm_vcpu *vcpu) return (unsigned long *)&vcpu->arch.hcr; } -static inline void vcpu_clear_wfe_traps(struct kvm_vcpu *vcpu) +static inline void vcpu_clear_wfx_traps(struct kvm_vcpu *vcpu) { vcpu->arch.hcr &= ~HCR_TWE; } -static inline void vcpu_set_wfe_traps(struct kvm_vcpu *vcpu) +static inline void vcpu_set_wfx_traps(struct kvm_vcpu *vcpu) { vcpu->arch.hcr |= HCR_TWE; } diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h index 6e92f6c7b1e4..5a542d801f07 100644 --- a/arch/arm64/include/asm/kvm_emulate.h +++ b/arch/arm64/include/asm/kvm_emulate.h @@ -87,14 +87,19 @@ static inline unsigned long *vcpu_hcr(struct kvm_vcpu *vcpu) return (unsigned long *)&vcpu->arch.hcr_el2; } -static inline void vcpu_clear_wfe_traps(struct kvm_vcpu *vcpu) +static inline void vcpu_clear_wfx_traps(struct kvm_vcpu *vcpu) { vcpu->arch.hcr_el2 &= ~HCR_TWE; + if (atomic_read(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe.vlpi_count)) + vcpu->arch.hcr_el2 &= ~HCR_TWI; + else + vcpu->arch.hcr_el2 |= HCR_TWI; } -static inline void vcpu_set_wfe_traps(struct kvm_vcpu *vcpu) +static inline void vcpu_set_wfx_traps(struct kvm_vcpu *vcpu) { vcpu->arch.hcr_el2 |= HCR_TWE; + vcpu->arch.hcr_el2 |= HCR_TWI; } static inline void vcpu_ptrauth_enable(struct kvm_vcpu *vcpu) -- cgit v1.2.3 From bf4b96bb542ee3fe913d0b9eb4d9c1046c429ac6 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Thu, 5 Dec 2019 18:06:51 +0000 Subject: KVM: arm64: Sanely ratelimit sysreg messages Currently kvm_pr_unimpl() is ratelimited, so print_sys_reg_instr() won't spam the console. However, someof its callers try to print some contextual information with kvm_err(), which is not ratelimited. This means that in some cases the context may be printed without the sysreg encoding, which isn't all that useful. Let's ensure that both are consistently printed together and ratelimited, by refactoring print_sys_reg_instr() so that some callers can provide it with an arbitrary format string. Signed-off-by: Mark Rutland Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20191205180652.18671-2-mark.rutland@arm.com --- arch/arm64/kvm/sys_regs.c | 12 ++++++------ arch/arm64/kvm/sys_regs.h | 17 +++++++++++++++-- 2 files changed, 21 insertions(+), 8 deletions(-) (limited to 'arch') diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 2071260a275b..e8bf08e09f78 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -2094,9 +2094,9 @@ static void unhandled_cp_access(struct kvm_vcpu *vcpu, WARN_ON(1); } - kvm_err("Unsupported guest CP%d access at: %08lx [%08lx]\n", - cp, *vcpu_pc(vcpu), *vcpu_cpsr(vcpu)); - print_sys_reg_instr(params); + print_sys_reg_msg(params, + "Unsupported guest CP%d access at: %08lx [%08lx]\n", + cp, *vcpu_pc(vcpu), *vcpu_cpsr(vcpu)); kvm_inject_undefined(vcpu); } @@ -2245,9 +2245,9 @@ static int emulate_sys_reg(struct kvm_vcpu *vcpu, if (likely(r)) { perform_access(vcpu, params, r); } else { - kvm_err("Unsupported guest sys_reg access at: %lx [%08lx]\n", - *vcpu_pc(vcpu), *vcpu_cpsr(vcpu)); - print_sys_reg_instr(params); + print_sys_reg_msg(params, + "Unsupported guest sys_reg access at: %lx [%08lx]\n", + *vcpu_pc(vcpu), *vcpu_cpsr(vcpu)); kvm_inject_undefined(vcpu); } return 1; diff --git a/arch/arm64/kvm/sys_regs.h b/arch/arm64/kvm/sys_regs.h index 9bca0312d798..5a6fc30f5989 100644 --- a/arch/arm64/kvm/sys_regs.h +++ b/arch/arm64/kvm/sys_regs.h @@ -62,11 +62,24 @@ struct sys_reg_desc { #define REG_HIDDEN_USER (1 << 0) /* hidden from userspace ioctls */ #define REG_HIDDEN_GUEST (1 << 1) /* hidden from guest */ -static inline void print_sys_reg_instr(const struct sys_reg_params *p) +static __printf(2, 3) +inline void print_sys_reg_msg(const struct sys_reg_params *p, + char *fmt, ...) { + va_list va; + + va_start(va, fmt); /* Look, we even formatted it for you to paste into the table! */ - kvm_pr_unimpl(" { Op0(%2u), Op1(%2u), CRn(%2u), CRm(%2u), Op2(%2u), func_%s },\n", + kvm_pr_unimpl("%pV { Op0(%2u), Op1(%2u), CRn(%2u), CRm(%2u), Op2(%2u), func_%s },\n", + &(struct va_format){ fmt, &va }, p->Op0, p->Op1, p->CRn, p->CRm, p->Op2, p->is_write ? "write" : "read"); + va_end(va); +} + +static inline void print_sys_reg_instr(const struct sys_reg_params *p) +{ + /* GCC warns on an empty format string */ + print_sys_reg_msg(p, "%s", ""); } static inline bool ignore_write(struct kvm_vcpu *vcpu, -- cgit v1.2.3 From 54ad68b7776043a77c9bf0a67d49cd9cb261a8e7 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Thu, 5 Dec 2019 18:06:52 +0000 Subject: KVM: arm64: Don't log IMP DEF sysreg traps We don't intend to support IMPLEMENATION DEFINED system registers, but have to trap them (and emulate them as UNDEFINED). These traps aren't interesting to the system administrator or to the KVM developers, so let's not bother logging when we do so. Signed-off-by: Mark Rutland Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20191205180652.18671-3-mark.rutland@arm.com --- arch/arm64/kvm/sys_regs.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'arch') diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index e8bf08e09f78..bd2ac3796d8d 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -2229,6 +2229,12 @@ int kvm_handle_cp14_32(struct kvm_vcpu *vcpu, struct kvm_run *run) NULL, 0); } +static bool is_imp_def_sys_reg(struct sys_reg_params *params) +{ + // See ARM DDI 0487E.a, section D12.3.2 + return params->Op0 == 3 && (params->CRn & 0b1011) == 0b1011; +} + static int emulate_sys_reg(struct kvm_vcpu *vcpu, struct sys_reg_params *params) { @@ -2244,6 +2250,8 @@ static int emulate_sys_reg(struct kvm_vcpu *vcpu, if (likely(r)) { perform_access(vcpu, params, r); + } else if (is_imp_def_sys_reg(params)) { + kvm_inject_undefined(vcpu); } else { print_sys_reg_msg(params, "Unsupported guest sys_reg access at: %lx [%08lx]\n", -- cgit v1.2.3 From 1ce74e96c2407df2b5867e5d45a70aacb8923c14 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Thu, 12 Dec 2019 09:40:49 +0000 Subject: KVM: arm64: Ensure 'params' is initialised when looking up sys register MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Commit 4b927b94d5df ("KVM: arm/arm64: vgic: Introduce find_reg_by_id()") introduced 'find_reg_by_id()', which looks up a system register only if the 'id' index parameter identifies a valid system register. As part of the patch, existing callers of 'find_reg()' were ported over to the new interface, but this breaks 'index_to_sys_reg_desc()' in the case that the initial lookup in the vCPU target table fails because we will then call into 'find_reg()' for the system register table with an uninitialised 'param' as the key to the lookup. GCC 10 is bright enough to spot this (amongst a tonne of false positives, but hey!): | arch/arm64/kvm/sys_regs.c: In function ‘index_to_sys_reg_desc.part.0.isra’: | arch/arm64/kvm/sys_regs.c:983:33: warning: ‘params.Op2’ may be used uninitialized in this function [-Wmaybe-uninitialized] | 983 | (u32)(x)->CRn, (u32)(x)->CRm, (u32)(x)->Op2); | [...] Revert the hunk of 4b927b94d5df which breaks 'index_to_sys_reg_desc()' so that the old behaviour of checking the index upfront is restored. Fixes: 4b927b94d5df ("KVM: arm/arm64: vgic: Introduce find_reg_by_id()") Signed-off-by: Will Deacon Signed-off-by: Marc Zyngier Cc: Link: https://lore.kernel.org/r/20191212094049.12437-1-will@kernel.org --- arch/arm64/kvm/sys_regs.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index bd2ac3796d8d..d78b726d4722 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -2364,8 +2364,11 @@ static const struct sys_reg_desc *index_to_sys_reg_desc(struct kvm_vcpu *vcpu, if ((id & KVM_REG_ARM_COPROC_MASK) != KVM_REG_ARM64_SYSREG) return NULL; + if (!index_to_params(id, ¶ms)) + return NULL; + table = get_target_table(vcpu->arch.target, true, &num); - r = find_reg_by_id(id, ¶ms, table, num); + r = find_reg(¶ms, table, num); if (!r) r = find_reg(¶ms, sys_reg_descs, ARRAY_SIZE(sys_reg_descs)); -- cgit v1.2.3