On Wed, Jan 08, 2025 at 10:37:57AM -0800, Jim Mattson wrote: > Surely, IBPB-on-VMexit is worse for performance than safe-RET?!? We don't need safe-RET with SRSO_USER_KERNEL_NO=1. And there's no safe-RET for virt only. So IBPB-on-VMEXIT is the next best thing. The good thing is, those machines have BpSpecReduce too so you won't be doing IBPB-on-VMEXIT either but what we're talking about here - BpSpecReduce. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette