[PATCH] arch/powerpc/kvm: kvmppc_core_vcpu_create_hv: check for kzalloc failure

[Kautuk Consul]

kvmppc_vcore_create() might not be able to allocate memory through
kzalloc. In that case the kvm->arch.online_vcores shouldn't be
incremented.
Add a check for kzalloc failure and return with -ENOMEM from
kvmppc_core_vcpu_create_hv().

Signed-off-by: Kautuk Consul <kcon...@linux.vnet.ibm.com>
---
 arch/powerpc/kvm/book3s_hv.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 6ba68dd6190b..e29ee755c920 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -2968,13 +2968,17 @@ static int kvmppc_core_vcpu_create_hv(struct kvm_vcpu 
*vcpu)
                        pr_devel("KVM: collision on id %u", id);
                        vcore = NULL;
                } else if (!vcore) {
+                       vcore = kvmppc_vcore_create(kvm,
+                                       id & ~(kvm->arch.smt_mode - 1));
+                       if (unlikely(!vcore)) {
+                               mutex_unlock(&kvm->lock);
+                               return -ENOMEM;
+                       }
+
                        /*
                         * Take mmu_setup_lock for mutual exclusion
                         * with kvmppc_update_lpcr().
                         */
-                       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++;
-- 
2.39.2