Intel's "DOITM" Security Feature Not Intended For Always-On Use, Linux Patches To Be Revised

Last week I wrote about Linux developers evaluating a new "DOITM" security mitigation for the latest Intel CPUs. While the cost for now of engaging the Data Operand Independent Timing Mode (DOITM) functionality is minimal, following internal Intel engineering discussions it looks like the Linux kernel patches will need to be re-worked with this functionality not intended to always be enabled...