Commit a76f8497 authored by Alexander Graf's avatar Alexander Graf Committed by Marcelo Tosatti
Browse files

KVM: PPC: Move Shadow MSR calculation to function 



We keep a copy of the MSR around that we use when we go into the guest context.

That copy is basically the normal process MSR flags OR some allowed guest
specified MSR flags. We also AND the external providers into this, so we get
traps on FPU usage when we haven't activated it on the host yet.

Currently this calculation is part of the set_msr function that we use whenever
we set the guest MSR value. With the external providers, we also have the case
that we don't modify the guest's MSR, but only want to update the shadow MSR.

So let's move the shadow MSR parts to a separate function that we then use
whenever we only need to update it. That way we don't accidently kvm_vcpu_block
within a preempt notifier context.

Signed-off-by: default avatarAlexander Graf <agraf@suse.de>
Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
parent f7adbba1

arch/powerpc/kvm/book3s.c

+21 −6
Original line number Diff line number Diff line
@@ -94,6 +94,23 @@ static u32 kvmppc_get_dec(struct kvm_vcpu *vcpu) 
}

#endif



static void kvmppc_recalc_shadow_msr(struct kvm_vcpu *vcpu)

{

	vcpu->arch.shadow_msr = vcpu->arch.msr;

	/* Guest MSR values */

	vcpu->arch.shadow_msr &= MSR_FE0 | MSR_FE1 | MSR_SF | MSR_SE |

				 MSR_BE | MSR_DE;

	/* Process MSR values */

	vcpu->arch.shadow_msr |= MSR_ME | MSR_RI | MSR_IR | MSR_DR | MSR_PR |

				 MSR_EE;

	/* External providers the guest reserved */

	vcpu->arch.shadow_msr |= (vcpu->arch.msr & vcpu->arch.guest_owned_ext);

	/* 64-bit Process MSR values */

#ifdef CONFIG_PPC_BOOK3S_64

	vcpu->arch.shadow_msr |= MSR_ISF | MSR_HV;

#endif

}



void kvmppc_set_msr(struct kvm_vcpu *vcpu, u64 msr)

{

	ulong old_msr = vcpu->arch.msr;
@@ -101,12 +118,10 @@ void kvmppc_set_msr(struct kvm_vcpu *vcpu, u64 msr) 
#ifdef EXIT_DEBUG

	printk(KERN_INFO "KVM: Set MSR to 0x%llx\n", msr);

#endif



	msr &= to_book3s(vcpu)->msr_mask;

	vcpu->arch.msr = msr;

	vcpu->arch.shadow_msr = msr | MSR_USER32;

	vcpu->arch.shadow_msr &= (MSR_FE0 | MSR_USER64 | MSR_SE | MSR_BE |

				  MSR_DE | MSR_FE1);

	vcpu->arch.shadow_msr |= (msr & vcpu->arch.guest_owned_ext);

	kvmppc_recalc_shadow_msr(vcpu);



	if (msr & (MSR_WE|MSR_POW)) {

		if (!vcpu->arch.pending_exceptions) {
@@ -610,7 +625,7 @@ static void kvmppc_giveup_ext(struct kvm_vcpu *vcpu, ulong msr) 


	vcpu->arch.guest_owned_ext &= ~msr;

	current->thread.regs->msr &= ~msr;

	kvmppc_set_msr(vcpu, vcpu->arch.msr);

	kvmppc_recalc_shadow_msr(vcpu);

}



/* Handle external providers (FPU, Altivec, VSX) */
@@ -664,7 +679,7 @@ static int kvmppc_handle_ext(struct kvm_vcpu *vcpu, unsigned int exit_nr, 


	vcpu->arch.guest_owned_ext |= msr;



	kvmppc_set_msr(vcpu, vcpu->arch.msr);

	kvmppc_recalc_shadow_msr(vcpu);



	return RESUME_GUEST;

}

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