[PATCH v4 06/21] KVM: arm64: Support SDEI_EVENT_CONTEXT hypercall
From: Gavin Shan <hidden>
Date: 2021-08-15 00:15:02
Also in:
kvmarm
Subsystem:
arm64 port (aarch64 architecture), kernel virtual machine for arm64 (kvm/arm64), the rest · Maintainers:
Catalin Marinas, Will Deacon, Marc Zyngier, Oliver Upton, Linus Torvalds
This supports SDEI_EVENT_CONTEXT hypercall. It's used by the guest to retrieved the original registers (R0 - R17) in its SDEI event handler. Those registers can be corrupted during the SDEI event delivery. Signed-off-by: Gavin Shan <redacted> --- arch/arm64/kvm/sdei.c | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+)
diff --git a/arch/arm64/kvm/sdei.c b/arch/arm64/kvm/sdei.c
index b022ce0a202b..b4162efda470 100644
--- a/arch/arm64/kvm/sdei.c
+++ b/arch/arm64/kvm/sdei.c@@ -270,6 +270,44 @@ static unsigned long kvm_sdei_hypercall_enable(struct kvm_vcpu *vcpu, return ret; } +static unsigned long kvm_sdei_hypercall_context(struct kvm_vcpu *vcpu) +{ + struct kvm *kvm = vcpu->kvm; + struct kvm_sdei_kvm *ksdei = kvm->arch.sdei; + struct kvm_sdei_vcpu *vsdei = vcpu->arch.sdei; + struct kvm_sdei_vcpu_regs *regs; + unsigned long index = smccc_get_arg1(vcpu); + unsigned long ret = SDEI_SUCCESS; + + /* Sanity check */ + if (!(ksdei && vsdei)) { + ret = SDEI_NOT_SUPPORTED; + goto out; + } + + if (index > ARRAY_SIZE(vsdei->state.critical_regs.regs)) { + ret = SDEI_INVALID_PARAMETERS; + goto out; + } + + /* Check if the pending event exists */ + spin_lock(&vsdei->lock); + if (!(vsdei->critical_event || vsdei->normal_event)) { + ret = SDEI_DENIED; + goto unlock; + } + + /* Fetch the requested register */ + regs = vsdei->critical_event ? &vsdei->state.critical_regs : + &vsdei->state.normal_regs; + ret = regs->regs[index]; + +unlock: + spin_unlock(&vsdei->lock); +out: + return ret; +} + int kvm_sdei_hypercall(struct kvm_vcpu *vcpu) { u32 func = smccc_get_function(vcpu);
@@ -290,6 +328,8 @@ int kvm_sdei_hypercall(struct kvm_vcpu *vcpu) ret = kvm_sdei_hypercall_enable(vcpu, false); break; case SDEI_1_0_FN_SDEI_EVENT_CONTEXT: + ret = kvm_sdei_hypercall_context(vcpu); + break; case SDEI_1_0_FN_SDEI_EVENT_COMPLETE: case SDEI_1_0_FN_SDEI_EVENT_COMPLETE_AND_RESUME: case SDEI_1_0_FN_SDEI_EVENT_UNREGISTER:
--
2.23.0