From e65733b5c59a1ea20324a03494364958bef3fc68 Mon Sep 17 00:00:00 2001 From: Oliver Upton Date: Tue, 4 Apr 2023 15:40:38 +0000 Subject: KVM: x86: Redefine 'longmode' as a flag for KVM_EXIT_HYPERCALL The 'longmode' field is a bit annoying as it blows an entire __u32 to represent a boolean value. Since other architectures are looking to add support for KVM_EXIT_HYPERCALL, now is probably a good time to clean it up. Redefine the field (and the remaining padding) as a set of flags. Preserve the existing ABI by using bit 0 to indicate if the guest was in long mode and requiring that the remaining 31 bits must be zero. Cc: Paolo Bonzini Acked-by: Sean Christopherson Signed-off-by: Oliver Upton Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20230404154050.2270077-2-oliver.upton@linux.dev --- include/uapi/linux/kvm.h | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index d77aef872a0a..dd42d7dfb86c 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -341,8 +341,13 @@ struct kvm_run { __u64 nr; __u64 args[6]; __u64 ret; - __u32 longmode; - __u32 pad; + + union { +#ifndef __KERNEL__ + __u32 longmode; +#endif + __u64 flags; + }; } hypercall; /* KVM_EXIT_TPR_ACCESS */ struct { -- cgit v1.2.3 From aac94968126beb9846c12a940f1302ece7849b4f Mon Sep 17 00:00:00 2001 From: Oliver Upton Date: Tue, 4 Apr 2023 15:40:41 +0000 Subject: KVM: arm64: Rename SMC/HVC call handler to reflect reality KVM handles SMCCC calls from virtual EL2 that use the SMC instruction since commit bd36b1a9eb5a ("KVM: arm64: nv: Handle SMCs taken from virtual EL2"). Thus, the function name of the handler no longer reflects reality. Normalize the name on SMCCC, since that's the only hypercall interface KVM supports in the first place. No fuctional change intended. Reviewed-by: Suzuki K Poulose Signed-off-by: Oliver Upton Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20230404154050.2270077-5-oliver.upton@linux.dev --- include/kvm/arm_hypercalls.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/kvm/arm_hypercalls.h b/include/kvm/arm_hypercalls.h index 1188f116cf4e..8f4e33bc43e8 100644 --- a/include/kvm/arm_hypercalls.h +++ b/include/kvm/arm_hypercalls.h @@ -6,7 +6,7 @@ #include -int kvm_hvc_call_handler(struct kvm_vcpu *vcpu); +int kvm_smccc_call_handler(struct kvm_vcpu *vcpu); static inline u32 smccc_get_function(struct kvm_vcpu *vcpu) { -- cgit v1.2.3 From fb88707dd39bd1d5ec4a058776de9ee99bcc7b72 Mon Sep 17 00:00:00 2001 From: Oliver Upton Date: Tue, 4 Apr 2023 15:40:44 +0000 Subject: KVM: arm64: Use a maple tree to represent the SMCCC filter Maple tree is an efficient B-tree implementation that is intended for storing non-overlapping intervals. Such a data structure is a good fit for the SMCCC filter as it is desirable to sparsely allocate the 32 bit function ID space. To that end, add a maple tree to kvm_arch and correctly init/teardown along with the VM. Wire in a test against the hypercall filter for HVCs which does nothing until the controls are exposed to userspace. Signed-off-by: Oliver Upton Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20230404154050.2270077-8-oliver.upton@linux.dev --- include/kvm/arm_hypercalls.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/kvm/arm_hypercalls.h b/include/kvm/arm_hypercalls.h index 8f4e33bc43e8..fe6c31575b05 100644 --- a/include/kvm/arm_hypercalls.h +++ b/include/kvm/arm_hypercalls.h @@ -43,6 +43,7 @@ static inline void smccc_set_retval(struct kvm_vcpu *vcpu, struct kvm_one_reg; void kvm_arm_init_hypercalls(struct kvm *kvm); +void kvm_arm_teardown_hypercalls(struct kvm *kvm); 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); -- cgit v1.2.3 From 821d935c87bc95253f82deec3cbb457ccf3de003 Mon Sep 17 00:00:00 2001 From: Oliver Upton Date: Tue, 4 Apr 2023 15:40:46 +0000 Subject: KVM: arm64: Introduce support for userspace SMCCC filtering As the SMCCC (and related specifications) march towards an 'everything and the kitchen sink' interface for interacting with a system it becomes less likely that KVM will support every related feature. We could do better by letting userspace have a crack at it instead. Allow userspace to define an 'SMCCC filter' that applies to both HVCs and SMCs initiated by the guest. Supporting both conduits with this interface is important for a couple of reasons. Guest SMC usage is table stakes for a nested guest, as HVCs are always taken to the virtual EL2. Additionally, guests may want to interact with a service on the secure side which can now be proxied by userspace. Signed-off-by: Oliver Upton Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20230404154050.2270077-10-oliver.upton@linux.dev --- include/kvm/arm_hypercalls.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include') diff --git a/include/kvm/arm_hypercalls.h b/include/kvm/arm_hypercalls.h index fe6c31575b05..2df152207ccd 100644 --- a/include/kvm/arm_hypercalls.h +++ b/include/kvm/arm_hypercalls.h @@ -49,4 +49,7 @@ 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); +int kvm_vm_smccc_has_attr(struct kvm *kvm, struct kvm_device_attr *attr); +int kvm_vm_smccc_set_attr(struct kvm *kvm, struct kvm_device_attr *attr); + #endif -- cgit v1.2.3