Some aspects of vcpu configuration can't be completed inside KVM_VCPU_INIT, but still change API behaviour visible to userspace.
Where such configuration choices affect the register list visible to userspace, we will need to track whether we have made a commitment to userspace regarding the list of vcpu registers. This patch adds a new hook kvm_arm_vcpu_finalize() to capture this commitment, along with a corresponding check kvm_arm_vcpu_finalized(). We commit to the register list when userspace reads it via KVM_GET_REG_LIST, or when the vcpu is fired up via KVM_RUN. kvm_arm_vcpu_finalize() is currently a no-op, but future patches will amend this to handle SVE on arm64. Signed-off-by: Dave Martin <[email protected]> --- arch/arm/include/asm/kvm_host.h | 4 ++++ arch/arm64/include/asm/kvm_host.h | 4 ++++ virt/kvm/arm/arm.c | 8 ++++++++ 3 files changed, 16 insertions(+) diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index ca56537..ab7c76b 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -360,4 +360,8 @@ static inline int kvm_arm_setup_stage2(struct kvm *kvm, unsigned long type) return 0; } +/* Commit to the set of vcpu registers currently configured: */ +static inline int kvm_arm_vcpu_finalize(struct kvm_vcpu *vcpu) { return 0; } +#define kvm_arm_vcpu_finalized(vcpu) true + #endif /* __ARM_KVM_HOST_H__ */ diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index d233855..015c2578 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -553,4 +553,8 @@ void kvm_arch_free_vm(struct kvm *kvm); int kvm_arm_setup_stage2(struct kvm *kvm, unsigned long type); +/* Commit to the set of vcpu registers currently configured: */ +static inline int kvm_arm_vcpu_finalize(struct kvm_vcpu *vcpu) { return 0; } +#define kvm_arm_vcpu_finalized(vcpu) true + #endif /* __ARM64_KVM_HOST_H__ */ diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c index 9e350fd3..12f9dc2 100644 --- a/virt/kvm/arm/arm.c +++ b/virt/kvm/arm/arm.c @@ -560,6 +560,10 @@ static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu) if (likely(vcpu->arch.has_run_once)) return 0; + ret = kvm_arm_vcpu_finalize(vcpu); + if (ret) + return ret; + vcpu->arch.has_run_once = true; if (likely(irqchip_in_kernel(kvm))) { @@ -1121,6 +1125,10 @@ long kvm_arch_vcpu_ioctl(struct file *filp, if (unlikely(!kvm_vcpu_initialized(vcpu))) break; + r = kvm_arm_vcpu_finalize(vcpu); + if (r) + break; + r = -EFAULT; if (copy_from_user(®_list, user_list, sizeof(reg_list))) break; -- 2.1.4 _______________________________________________ kvmarm mailing list [email protected] https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
