From 85bd0ba1ff9875798fad94218b627ea9f768f3c3 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Sun, 21 Jan 2018 16:42:56 +0000 Subject: arm/arm64: KVM: Add PSCI version selection API 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 --- arch/arm64/include/asm/kvm_host.h | 3 +++ arch/arm64/include/uapi/asm/kvm.h | 6 ++++++ arch/arm64/kvm/guest.c | 14 +++++++++++++- 3 files changed, 22 insertions(+), 1 deletion(-) (limited to 'arch/arm64') diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index ab46bc70add6..469de8acd06f 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -75,6 +75,9 @@ struct kvm_arch { /* Interrupt controller */ struct vgic_dist vgic; + + /* Mandated version of PSCI */ + u32 psci_version; }; #define KVM_NR_MEM_OBJS 40 diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index 9abbf3044654..04b3256f8e6d 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -206,6 +206,12 @@ 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 diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index 959e50d2588c..56a0260ceb11 100644 --- 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 *vcpu, const struct kvm_one_reg *reg) 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_vcpu *vcpu, u64 __user *uindices) 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 *vcpu, const struct kvm_one_reg *reg) 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 *vcpu, const struct kvm_one_reg *reg) 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); -- cgit v1.2.3