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/arm64/include/uapi/asm/kvm.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'arch/arm64/include/uapi/asm/kvm.h') 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]; -- cgit v1.2.3-59-g8ed1b 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 ++++++ include/uapi/linux/kvm.h | 2 ++ virt/kvm/arm/pvtime.c | 59 +++++++++++++++++++++++++++++++++++++++ 5 files changed, 79 insertions(+) (limited to 'arch/arm64/include/uapi/asm/kvm.h') 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; diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 52641d8ca9e8..a540c8357049 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -1227,6 +1227,8 @@ enum kvm_device_type { #define KVM_DEV_TYPE_ARM_VGIC_ITS KVM_DEV_TYPE_ARM_VGIC_ITS KVM_DEV_TYPE_XIVE, #define KVM_DEV_TYPE_XIVE KVM_DEV_TYPE_XIVE + KVM_DEV_TYPE_ARM_PV_TIME, +#define KVM_DEV_TYPE_ARM_PV_TIME KVM_DEV_TYPE_ARM_PV_TIME KVM_DEV_TYPE_MAX, }; diff --git a/virt/kvm/arm/pvtime.c b/virt/kvm/arm/pvtime.c index b90b3a7bea85..1e0f4c284888 100644 --- a/virt/kvm/arm/pvtime.c +++ b/virt/kvm/arm/pvtime.c @@ -2,7 +2,9 @@ // Copyright (C) 2019 Arm Ltd. #include +#include +#include #include #include @@ -70,3 +72,60 @@ gpa_t kvm_init_stolen_time(struct kvm_vcpu *vcpu) return base; } + +int kvm_arm_pvtime_set_attr(struct kvm_vcpu *vcpu, + struct kvm_device_attr *attr) +{ + u64 __user *user = (u64 __user *)attr->addr; + struct kvm *kvm = vcpu->kvm; + u64 ipa; + int ret = 0; + int idx; + + if (attr->attr != KVM_ARM_VCPU_PVTIME_IPA) + return -ENXIO; + + if (get_user(ipa, user)) + return -EFAULT; + if (!IS_ALIGNED(ipa, 64)) + return -EINVAL; + if (vcpu->arch.steal.base != GPA_INVALID) + return -EEXIST; + + /* Check the address is in a valid memslot */ + idx = srcu_read_lock(&kvm->srcu); + if (kvm_is_error_hva(gfn_to_hva(kvm, ipa >> PAGE_SHIFT))) + ret = -EINVAL; + srcu_read_unlock(&kvm->srcu, idx); + + if (!ret) + vcpu->arch.steal.base = ipa; + + return ret; +} + +int kvm_arm_pvtime_get_attr(struct kvm_vcpu *vcpu, + struct kvm_device_attr *attr) +{ + u64 __user *user = (u64 __user *)attr->addr; + u64 ipa; + + if (attr->attr != KVM_ARM_VCPU_PVTIME_IPA) + return -ENXIO; + + ipa = vcpu->arch.steal.base; + + if (put_user(ipa, user)) + return -EFAULT; + return 0; +} + +int kvm_arm_pvtime_has_attr(struct kvm_vcpu *vcpu, + struct kvm_device_attr *attr) +{ + switch (attr->attr) { + case KVM_ARM_VCPU_PVTIME_IPA: + return 0; + } + return -ENXIO; +} -- cgit v1.2.3-59-g8ed1b