Errata patches for the kernel have been released for OpenBSD 6.4 and 6.5. Resume forgot to restore MSR/PAT configuration.
Binary updates for the amd64 platform are available via the syspatch utility. Source code patches can be found on the respective errata page: https://www.openbsd.org/errata64.html https://www.openbsd.org/errata65.html As these affect the kernel, a reboot will be needed after patching.
