On 3/20/23 18:02, andrew.cooper3@xxxxxxxxxx wrote: > There are fewer cases where a non-IST #VE ends up in a re-entrant fault > (IIRC, you can still manage it by unmapping the entry stack), but you're > still trusting the outer hypervisor to not e.g. unmap the SYSCALL entry > point. This is a general weakness of #VE. But, the current Linux TDX guest implementation is not vulnerable to it. If the host unmaps something unexpectedly, the guest will just die because of ATTR_SEPT_VE_DISABLE. No #VE: > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/x86/coco/tdx/tdx.c#n216
