diff options
author | Marc Zyngier <marc.zyngier@arm.com> | 2018-01-21 16:42:56 +0000 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-05-09 09:50:19 +0200 |
commit | b8beca48a5504a790f3e308adcb965c6d9c657dc (patch) | |
tree | ac8064736f093fdc047f3b062f7b0501d85adf73 /arch/arm/kvm | |
parent | fcbc8d0e7dbef92a6b611a6d3d1ed8ea228464a0 (diff) |
arm/arm64: KVM: Add PSCI version selection API
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 <cdall@kernel.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/arm/kvm')
-rw-r--r-- | arch/arm/kvm/guest.c | 13 | ||||
-rw-r--r-- | arch/arm/kvm/psci.c | 60 |
2 files changed, 73 insertions, 0 deletions
diff --git a/arch/arm/kvm/guest.c b/arch/arm/kvm/guest.c index 9aca92074f85..630117d2e8bd 100644 --- a/arch/arm/kvm/guest.c +++ b/arch/arm/kvm/guest.c @@ -22,6 +22,7 @@ #include <linux/module.h> #include <linux/vmalloc.h> #include <linux/fs.h> +#include <kvm/arm_psci.h> #include <asm/cputype.h> #include <asm/uaccess.h> #include <asm/kvm.h> @@ -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_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; @@ -214,6 +221,9 @@ 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); @@ -230,6 +240,9 @@ 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); diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c index 3d962257c166..8a9c654f4f87 100644 --- a/arch/arm/kvm/psci.c +++ b/arch/arm/kvm/psci.c @@ -18,6 +18,7 @@ #include <linux/arm-smccc.h> #include <linux/preempt.h> #include <linux/kvm_host.h> +#include <linux/uaccess.h> #include <linux/wait.h> #include <asm/cputype.h> @@ -425,3 +426,62 @@ int kvm_hvc_call_handler(struct kvm_vcpu *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; +} |