From 946cf44ac6ce61378ea02386d39394a06d502f28 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Mon, 12 Apr 2021 11:48:44 +1000 Subject: [PATCH] KVM: PPC: Book3S HV: Ensure MSR[ME] is always set in guest MSR Rather than add the ME bit to the MSR at guest entry, make it clear that the hypervisor does not allow the guest to clear the bit. The ME set is kept in guest entry for now, but a future patch will warn if it's not present. Signed-off-by: Nicholas Piggin Reviewed-by: Daniel Axtens Reviewed-by: Fabiano Rosas Acked-by: Paul Mackerras Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210412014845.1517916-12-npiggin@gmail.com --- arch/powerpc/kvm/book3s_hv_builtin.c | 3 +++ arch/powerpc/kvm/book3s_hv_nested.c | 4 +++- 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c index 158d309b42a38..41cb03d0bde45 100644 --- a/arch/powerpc/kvm/book3s_hv_builtin.c +++ b/arch/powerpc/kvm/book3s_hv_builtin.c @@ -662,6 +662,9 @@ static void kvmppc_end_cede(struct kvm_vcpu *vcpu) void kvmppc_set_msr_hv(struct kvm_vcpu *vcpu, u64 msr) { + /* Guest must always run with ME enabled. */ + msr = msr | MSR_ME; + /* * Check for illegal transactional state bit combination * and if we find it, force the TS field to a safe state. diff --git a/arch/powerpc/kvm/book3s_hv_nested.c b/arch/powerpc/kvm/book3s_hv_nested.c index d14fe32f167b8..fb03085c902ba 100644 --- a/arch/powerpc/kvm/book3s_hv_nested.c +++ b/arch/powerpc/kvm/book3s_hv_nested.c @@ -343,7 +343,9 @@ long kvmhv_enter_nested_guest(struct kvm_vcpu *vcpu) vcpu->arch.nested = l2; vcpu->arch.nested_vcpu_id = l2_hv.vcpu_token; vcpu->arch.regs = l2_regs; - vcpu->arch.shregs.msr = vcpu->arch.regs.msr; + + /* Guest must always run with ME enabled. */ + vcpu->arch.shregs.msr = vcpu->arch.regs.msr | MSR_ME; sanitise_hv_regs(vcpu, &l2_hv); restore_hv_regs(vcpu, &l2_hv); -- 2.30.2