From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AB8JxZoPfvzoTOSZhMsn7q5UK8NYJkl5cd90XkGFHj29gN7xuwkDOHKnKGuiUtT4IghmE2EEu1k8 ARC-Seal: i=1; a=rsa-sha256; t=1525767397; cv=none; d=google.com; s=arc-20160816; b=A3xdQ9Y/cX/W/X/y66AA3JmBjNmrC51RMnOOs1ktRwE4WDNdfffcdVqySyX0Axsr6K ffPGsUlhgbJTcEc/KLx0Pto4mJ4Ko39ARIxYhCWs0+LQljXKpEJr3vU18KMqFionW7Ix P5aZJgmVvWzQpDtjvIYtbkuaXKwmBADkcz8OtN6iG2ls0G9vcZIWbadJMW606n+5yjeC 586LR6u5X4MMZfsruQ9v0jA+qdT8gcEVZbtFlua3u5iqIsopC0owKFRLfUUWVKfXOxMC FXM4pdA+ltkWo9LhO2SR6bXJJsUXH+Cw4etuI8TZ8a6DRdqaakc75lEfN35fzPkZ/1rs X+rw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:dkim-signature:arc-authentication-results; bh=QqQCZOdweG9++EZQyf006LL07irx/9Hh9OE2kA5/THM=; b=iqVEOr8ulc35P5BHpBXnn8sgD9lWkzoKk1m/k/d1x8LKBP4QB0xTIckNJe0Ohy0rP8 OVVC7ICRaqnB2wJlcm46skcKArzIET6pKJ9+CULj4x90htUUDbxBfUngDfm+oqSdvIsx ZfvYuA2L0rsJjEakpS5PdtEPDNIKNqq3ESv8lpH3WdAA1yDpMaiR2rr87ZHKuVcQrRCR a7OWzkJmYazpTji/N7Y+cs3Tn+rKA0kuDc1LOVZiWEIK1L+0+0T4EbcgnbVlDGIflyjm wjg3Rvf7kr4n7ct6sZ/CVCz+SeyLPCHim7KpJj3ih6Bt+i7xWrQSrg5deWiA5Wa/kB+j pDjg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=ZtT6VMQZ; spf=pass (google.com: domain of srs0=4in3=h3=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=4In3=H3=linuxfoundation.org=gregkh@kernel.org Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=ZtT6VMQZ; spf=pass (google.com: domain of srs0=4in3=h3=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=4In3=H3=linuxfoundation.org=gregkh@kernel.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Christoffer Dall , Marc Zyngier Subject: [PATCH 4.9 04/32] arm/arm64: KVM: Add PSCI version selection API Date: Tue, 8 May 2018 10:10:44 +0200 Message-Id: <20180508074009.435585896@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180508074008.800421598@linuxfoundation.org> References: <20180508074008.800421598@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1599883074299462777?= X-GMAIL-MSGID: =?utf-8?q?1599883074299462777?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Marc Zyngier commit 85bd0ba1ff9875798fad94218b627ea9f768f3c3 upstream. Although we've implemented PSCI 0.1, 0.2 and 1.0, we expose either 0.1 or 1.0 to a guest, defaulting to the latest version of the PSCI implementation that is compatible with the requested version. This is no different from doing a firmware upgrade on KVM. But in order to give a chance to hypothetical badly implemented guests that would have a fit by discovering something other than PSCI 0.2, let's provide a new API that allows userspace to pick one particular version of the API. This is implemented as a new class of "firmware" registers, where we expose the PSCI version. This allows the PSCI version to be save/restored as part of a guest migration, and also set to any supported version if the guest requires it. Cc: stable@vger.kernel.org #4.16 Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier Signed-off-by: Greg Kroah-Hartman --- Documentation/virtual/kvm/api.txt | 9 ++++ Documentation/virtual/kvm/arm/psci.txt | 30 ++++++++++++++++ arch/arm/include/asm/kvm_host.h | 3 + arch/arm/include/uapi/asm/kvm.h | 6 +++ arch/arm/kvm/guest.c | 13 +++++++ arch/arm/kvm/psci.c | 60 +++++++++++++++++++++++++++++++++ arch/arm64/include/asm/kvm_host.h | 3 + arch/arm64/include/uapi/asm/kvm.h | 6 +++ arch/arm64/kvm/guest.c | 14 +++++++ include/kvm/arm_psci.h | 16 +++++++- 10 files changed, 156 insertions(+), 4 deletions(-) create mode 100644 Documentation/virtual/kvm/arm/psci.txt --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -2118,6 +2118,9 @@ ARM 32-bit VFP control registers have th ARM 64-bit FP registers have the following id bit patterns: 0x4030 0000 0012 0 +ARM firmware pseudo-registers have the following bit pattern: + 0x4030 0000 0014 + arm64 registers are mapped using the lower 32 bits. The upper 16 of that is the register group type, or coprocessor number: @@ -2134,6 +2137,9 @@ arm64 CCSIDR registers are demultiplexed arm64 system registers have the following id bit patterns: 0x6030 0000 0013 +arm64 firmware pseudo-registers have the following bit pattern: + 0x6030 0000 0014 + MIPS registers are mapped using the lower 32 bits. The upper 16 of that is the register group type: @@ -2656,7 +2662,8 @@ Possible features: and execute guest code when KVM_RUN is called. - KVM_ARM_VCPU_EL1_32BIT: Starts the CPU in a 32bit mode. Depends on KVM_CAP_ARM_EL1_32BIT (arm64 only). - - KVM_ARM_VCPU_PSCI_0_2: Emulate PSCI v0.2 for the CPU. + - KVM_ARM_VCPU_PSCI_0_2: Emulate PSCI v0.2 (or a future revision + backward compatible with v0.2) for the CPU. Depends on KVM_CAP_ARM_PSCI_0_2. - KVM_ARM_VCPU_PMU_V3: Emulate PMUv3 for the CPU. Depends on KVM_CAP_ARM_PMU_V3. --- /dev/null +++ b/Documentation/virtual/kvm/arm/psci.txt @@ -0,0 +1,30 @@ +KVM implements the PSCI (Power State Coordination Interface) +specification in order to provide services such as CPU on/off, reset +and power-off to the guest. + +The PSCI specification is regularly updated to provide new features, +and KVM implements these updates if they make sense from a virtualization +point of view. + +This means that a guest booted on two different versions of KVM can +observe two different "firmware" revisions. This could cause issues if +a given guest is tied to a particular PSCI revision (unlikely), or if +a migration causes a different PSCI version to be exposed out of the +blue to an unsuspecting guest. + +In order to remedy this situation, KVM exposes a set of "firmware +pseudo-registers" that can be manipulated using the GET/SET_ONE_REG +interface. These registers can be saved/restored by userspace, and set +to a convenient value if required. + +The following register is defined: + +* KVM_REG_ARM_PSCI_VERSION: + + - Only valid if the vcpu has the KVM_ARM_VCPU_PSCI_0_2 feature set + (and thus has already been initialized) + - Returns the current PSCI version on GET_ONE_REG (defaulting to the + highest PSCI version implemented by KVM and compatible with v0.2) + - Allows any PSCI version implemented by KVM and compatible with + v0.2 to be set with SET_ONE_REG + - Affects the whole VM (even if the register view is per-vcpu) --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -78,6 +78,9 @@ struct kvm_arch { /* Interrupt controller */ struct vgic_dist vgic; int max_vcpus; + + /* Mandated version of PSCI */ + u32 psci_version; }; #define KVM_NR_MEM_OBJS 40 --- a/arch/arm/include/uapi/asm/kvm.h +++ b/arch/arm/include/uapi/asm/kvm.h @@ -173,6 +173,12 @@ struct kvm_arch_memory_slot { #define KVM_REG_ARM_VFP_FPINST 0x1009 #define KVM_REG_ARM_VFP_FPINST2 0x100A +/* KVM-as-firmware specific pseudo-registers */ +#define KVM_REG_ARM_FW (0x0014 << KVM_REG_ARM_COPROC_SHIFT) +#define KVM_REG_ARM_FW_REG(r) (KVM_REG_ARM | KVM_REG_SIZE_U64 | \ + KVM_REG_ARM_FW | ((r) & 0xffff)) +#define KVM_REG_ARM_PSCI_VERSION KVM_REG_ARM_FW_REG(0) + /* Device Control API: ARM VGIC */ #define KVM_DEV_ARM_VGIC_GRP_ADDR 0 #define KVM_DEV_ARM_VGIC_GRP_DIST_REGS 1 --- a/arch/arm/kvm/guest.c +++ b/arch/arm/kvm/guest.c @@ -22,6 +22,7 @@ #include #include #include +#include #include #include #include @@ -176,6 +177,7 @@ static unsigned long num_core_regs(void) unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu) { return num_core_regs() + kvm_arm_num_coproc_regs(vcpu) + + kvm_arm_get_fw_num_regs(vcpu) + NUM_TIMER_REGS; } @@ -196,6 +198,11 @@ int kvm_arm_copy_reg_indices(struct kvm_ uindices++; } + ret = kvm_arm_copy_fw_reg_indices(vcpu, uindices); + if (ret) + return ret; + uindices += kvm_arm_get_fw_num_regs(vcpu); + ret = copy_timer_indices(vcpu, uindices); if (ret) return ret; @@ -214,6 +221,9 @@ int kvm_arm_get_reg(struct kvm_vcpu *vcp if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE) return get_core_reg(vcpu, reg); + if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_FW) + return kvm_arm_get_fw_reg(vcpu, reg); + if (is_timer_reg(reg->id)) return get_timer_reg(vcpu, reg); @@ -230,6 +240,9 @@ int kvm_arm_set_reg(struct kvm_vcpu *vcp if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE) return set_core_reg(vcpu, reg); + if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_FW) + return kvm_arm_set_fw_reg(vcpu, reg); + if (is_timer_reg(reg->id)) return set_timer_reg(vcpu, reg); --- a/arch/arm/kvm/psci.c +++ b/arch/arm/kvm/psci.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include @@ -425,3 +426,62 @@ int kvm_hvc_call_handler(struct kvm_vcpu smccc_set_retval(vcpu, val, 0, 0, 0); return 1; } + +int kvm_arm_get_fw_num_regs(struct kvm_vcpu *vcpu) +{ + return 1; /* PSCI version */ +} + +int kvm_arm_copy_fw_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices) +{ + if (put_user(KVM_REG_ARM_PSCI_VERSION, uindices)) + return -EFAULT; + + return 0; +} + +int kvm_arm_get_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) +{ + if (reg->id == KVM_REG_ARM_PSCI_VERSION) { + void __user *uaddr = (void __user *)(long)reg->addr; + u64 val; + + val = kvm_psci_version(vcpu, vcpu->kvm); + if (copy_to_user(uaddr, &val, KVM_REG_SIZE(reg->id))) + return -EFAULT; + + return 0; + } + + return -EINVAL; +} + +int kvm_arm_set_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) +{ + if (reg->id == KVM_REG_ARM_PSCI_VERSION) { + void __user *uaddr = (void __user *)(long)reg->addr; + bool wants_02; + u64 val; + + if (copy_from_user(&val, uaddr, KVM_REG_SIZE(reg->id))) + return -EFAULT; + + wants_02 = test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features); + + switch (val) { + case KVM_ARM_PSCI_0_1: + if (wants_02) + return -EINVAL; + vcpu->kvm->arch.psci_version = val; + return 0; + case KVM_ARM_PSCI_0_2: + case KVM_ARM_PSCI_1_0: + if (!wants_02) + return -EINVAL; + vcpu->kvm->arch.psci_version = val; + return 0; + } + } + + return -EINVAL; +} --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -73,6 +73,9 @@ struct kvm_arch { /* Timer */ struct arch_timer_kvm timer; + + /* Mandated version of PSCI */ + u32 psci_version; }; #define KVM_NR_MEM_OBJS 40 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -195,6 +195,12 @@ struct kvm_arch_memory_slot { #define KVM_REG_ARM_TIMER_CNT ARM64_SYS_REG(3, 3, 14, 3, 2) #define KVM_REG_ARM_TIMER_CVAL ARM64_SYS_REG(3, 3, 14, 0, 2) +/* KVM-as-firmware specific pseudo-registers */ +#define KVM_REG_ARM_FW (0x0014 << KVM_REG_ARM_COPROC_SHIFT) +#define KVM_REG_ARM_FW_REG(r) (KVM_REG_ARM64 | KVM_REG_SIZE_U64 | \ + KVM_REG_ARM_FW | ((r) & 0xffff)) +#define KVM_REG_ARM_PSCI_VERSION KVM_REG_ARM_FW_REG(0) + /* Device Control API: ARM VGIC */ #define KVM_DEV_ARM_VGIC_GRP_ADDR 0 #define KVM_DEV_ARM_VGIC_GRP_DIST_REGS 1 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -25,6 +25,7 @@ #include #include #include +#include #include #include #include @@ -205,7 +206,7 @@ static int get_timer_reg(struct kvm_vcpu unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu) { return num_core_regs() + kvm_arm_num_sys_reg_descs(vcpu) - + NUM_TIMER_REGS; + + kvm_arm_get_fw_num_regs(vcpu) + NUM_TIMER_REGS; } /** @@ -225,6 +226,11 @@ int kvm_arm_copy_reg_indices(struct kvm_ uindices++; } + ret = kvm_arm_copy_fw_reg_indices(vcpu, uindices); + if (ret) + return ret; + uindices += kvm_arm_get_fw_num_regs(vcpu); + ret = copy_timer_indices(vcpu, uindices); if (ret) return ret; @@ -243,6 +249,9 @@ int kvm_arm_get_reg(struct kvm_vcpu *vcp if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE) return get_core_reg(vcpu, reg); + if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_FW) + return kvm_arm_get_fw_reg(vcpu, reg); + if (is_timer_reg(reg->id)) return get_timer_reg(vcpu, reg); @@ -259,6 +268,9 @@ int kvm_arm_set_reg(struct kvm_vcpu *vcp if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE) return set_core_reg(vcpu, reg); + if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_FW) + return kvm_arm_set_fw_reg(vcpu, reg); + if (is_timer_reg(reg->id)) return set_timer_reg(vcpu, reg); --- a/include/kvm/arm_psci.h +++ b/include/kvm/arm_psci.h @@ -37,10 +37,15 @@ static inline int kvm_psci_version(struc * Our PSCI implementation stays the same across versions from * v0.2 onward, only adding the few mandatory functions (such * as FEATURES with 1.0) that are required by newer - * revisions. It is thus safe to return the latest. + * revisions. It is thus safe to return the latest, unless + * userspace has instructed us otherwise. */ - if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features)) + if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features)) { + if (vcpu->kvm->arch.psci_version) + return vcpu->kvm->arch.psci_version; + return KVM_ARM_PSCI_LATEST; + } return KVM_ARM_PSCI_0_1; } @@ -48,4 +53,11 @@ static inline int kvm_psci_version(struc int kvm_hvc_call_handler(struct kvm_vcpu *vcpu); +struct kvm_one_reg; + +int kvm_arm_get_fw_num_regs(struct kvm_vcpu *vcpu); +int kvm_arm_copy_fw_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices); +int kvm_arm_get_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg); +int kvm_arm_set_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg); + #endif /* __KVM_ARM_PSCI_H__ */