Greg Kroah-Hartman has released six new stable kernels to address the Zenbleed vulnerability for AMD processors: 6.4.6, 6.1.41,
5.15.122, 5.10.187, 5.4.250, and 4.19.289. “All AMD processor users of the
[…] kernel series who have not updated
their microcode to the latest version, must upgrade.“

Source: LWN.net – Stable kernels to address Zenbleed released