KVM: PPC: Book3S HV: Fix spinlock/mutex ordering issue in kvmppc_set_lpcr()

[mirror_ubuntu-bionic-kernel.git] / arch / powerpc / kvm / book3s_hv.c

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index de4018a1bc4bd290ecd0e970bd51960b281497c3..b2731933f80775e87bba59a53ee265a013298ad4 100644 (file)
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -942,20 +942,20 @@ static int kvm_arch_vcpu_ioctl_set_sregs_hv(struct kvm_vcpu *vcpu,
 static void kvmppc_set_lpcr(struct kvm_vcpu *vcpu, u64 new_lpcr,
                bool preserve_top32)
 {
+       struct kvm *kvm = vcpu->kvm;
        struct kvmppc_vcore *vc = vcpu->arch.vcore;
        u64 mask;
 
+       mutex_lock(&kvm->lock);
        spin_lock(&vc->lock);
        /*
         * If ILE (interrupt little-endian) has changed, update the
         * MSR_LE bit in the intr_msr for each vcpu in this vcore.
         */
        if ((new_lpcr & LPCR_ILE) != (vc->lpcr & LPCR_ILE)) {
-               struct kvm *kvm = vcpu->kvm;
                struct kvm_vcpu *vcpu;
                int i;
 
-               mutex_lock(&kvm->lock);
                kvm_for_each_vcpu(i, vcpu, kvm) {
                        if (vcpu->arch.vcore != vc)
                                continue;
@@ -964,7 +964,6 @@ static void kvmppc_set_lpcr(struct kvm_vcpu *vcpu, u64 new_lpcr,
                        else
                                vcpu->arch.intr_msr &= ~MSR_LE;
                }
-               mutex_unlock(&kvm->lock);
        }
 
        /*
@@ -981,6 +980,7 @@ static void kvmppc_set_lpcr(struct kvm_vcpu *vcpu, u64 new_lpcr,
                mask &= 0xFFFFFFFF;
        vc->lpcr = (vc->lpcr & ~mask) | (new_lpcr & mask);
        spin_unlock(&vc->lock);
+       mutex_unlock(&kvm->lock);
 }
 
 static int kvmppc_get_one_reg_hv(struct kvm_vcpu *vcpu, u64 id,