From 7a08c2740f07fb8c3769d1f137721835ead7652f Mon Sep 17 00:00:00 2001 From: Alexander Graf Date: Thu, 16 Aug 2012 13:10:16 +0200 Subject: [PATCH] KVM: PPC: BookE: Support FPU on non-hv systems When running on HV aware hosts, we can not trap when the guest sets the FP bit, so we just let it do so when it wants to, because it has full access to MSR. For non-HV aware hosts with an FPU (like 440), we need to also adjust the shadow MSR though. Otherwise the guest gets an FP unavailable trap even when it really enabled the FP bit in MSR. Signed-off-by: Alexander Graf --- arch/powerpc/kvm/booke.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c index 959aae96..5f0476a 100644 --- a/arch/powerpc/kvm/booke.c +++ b/arch/powerpc/kvm/booke.c @@ -122,6 +122,16 @@ static void kvmppc_vcpu_sync_spe(struct kvm_vcpu *vcpu) } #endif +static void kvmppc_vcpu_sync_fpu(struct kvm_vcpu *vcpu) +{ +#if defined(CONFIG_PPC_FPU) && !defined(CONFIG_KVM_BOOKE_HV) + /* We always treat the FP bit as enabled from the host + perspective, so only need to adjust the shadow MSR */ + vcpu->arch.shadow_msr &= ~MSR_FP; + vcpu->arch.shadow_msr |= vcpu->arch.shared->msr & MSR_FP; +#endif +} + /* * Helper function for "full" MSR writes. No need to call this if only * EE/CE/ME/DE/RI are changing. @@ -138,6 +148,7 @@ void kvmppc_set_msr(struct kvm_vcpu *vcpu, u32 new_msr) kvmppc_mmu_msr_notify(vcpu, old_msr); kvmppc_vcpu_sync_spe(vcpu); + kvmppc_vcpu_sync_fpu(vcpu); } static void kvmppc_booke_queue_irqprio(struct kvm_vcpu *vcpu, -- 2.7.4