[PATCHv3 6/7] KVM: PPC: Book3S HV: Fix error handling during vcore create

["Ritesh Harjani (IBM)" <ritesh.list@gmail.com>]

kvmppc_vcore_create() can fail and return NULL, this patch fixes the
error handling when this happens.

vcore and online_vcores count should only be updated when vcore was
actually created, otherwise it's state gets messed up for the VM run.

Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
---
 arch/powerpc/kvm/book3s_hv.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 22283d46e8fe..e39491dfb975 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -3090,10 +3090,12 @@ static int kvmppc_core_vcpu_create_hv(struct kvm_vcpu *vcpu)
 			err = -ENOMEM;
 			vcore = kvmppc_vcore_create(kvm,
 					id & ~(kvm->arch.smt_mode - 1));
-			mutex_lock(&kvm->arch.mmu_setup_lock);
-			kvm->arch.vcores[core] = vcore;
-			kvm->arch.online_vcores++;
-			mutex_unlock(&kvm->arch.mmu_setup_lock);
+			if (vcore) {
+				mutex_lock(&kvm->arch.mmu_setup_lock);
+				kvm->arch.vcores[core] = vcore;
+				kvm->arch.online_vcores++;
+				mutex_unlock(&kvm->arch.mmu_setup_lock);
+			}
 		}
 	}
 
-- 
2.39.5