Intel TDX has been found to require less cache flushing than previously thought, leading to performance improvements.

It Turns Out Intel TDX Doesn't Need So Much Cache Flushing Intel Trust Domain Extensions (TDX) for confidential computing with VMs has assumed the need to perform cache flushing when transitioning memory between KeyIDs used by the total memory encryption (MKTME) for unique AES encryption keys. But it's turned out to be unneeded and the Linux kernel is working now to reduce the excessive cache flushing... https://www.phoronix.com/news/Intel-TDX-Less-Cache-Flushing

It Turns Out Intel TDX Doesn't Need So Much Cache Flushing https://www.phoronix.com/news/Intel-TDX-Less-Cache-Flushing