Encryption key namespace for containerized workloads

In general, techniques are described for an encryption key namespace of a kernel, executed by a host computing device, the encryption key namespace having a configuration file that stores an association of a key identifier and a container identifier by which the host computing device can obtain a data encryption key to use for decrypting/encrypting data for the container identified by the container identifier. In this way, a user may associate a container (or container image) with a unique key identifier. By configuring this association in the encryption key namespace for the container, the container may be identified and automatically associated with a key identifier for the appropriate key for decrypting/encrypting data for the container. The host computing device may then obtain, from a key management service, the key using the key identifier.