diff options
Diffstat (limited to 'arch/s390/kvm/kvm-s390.c')
| -rw-r--r-- | arch/s390/kvm/kvm-s390.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index da3dabda1a12..76ad6408cb2c 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -2384,7 +2384,16 @@ static int kvm_s390_vm_mem_op(struct kvm *kvm, struct kvm_s390_mem_op *mop) return -EINVAL; if (mop->size > MEM_OP_MAX_SIZE) return -E2BIG; - if (kvm_s390_pv_is_protected(kvm)) + /* + * This is technically a heuristic only, if the kvm->lock is not + * taken, it is not guaranteed that the vm is/remains non-protected. + * This is ok from a kernel perspective, wrongdoing is detected + * on the access, -EFAULT is returned and the vm may crash the + * next time it accesses the memory in question. + * There is no sane usecase to do switching and a memop on two + * different CPUs at the same time. + */ + if (kvm_s390_pv_get_handle(kvm)) return -EINVAL; if (mop->flags & KVM_S390_MEMOP_F_SKEY_PROTECTION) { if (access_key_invalid(mop->key)) |