On July 6, 2025 2:22:13 AM PDT, David Laight <david.laight.linux@xxxxxxxxx> wrote: >On Tue, 01 Jul 2025 19:06:10 -0700 >"H. Peter Anvin" <hpa@xxxxxxxxx> wrote: >... >> Note: for a FRED system, ERETU can generate #SS for a non-canonical user space >> RSP even in the absence of LASS, so if that is not currently handled that is an active bug. > >Is that a fault in kernel space, or a fault in user space. > >Some of the traps for 'iret' happen after the transition to user space, >so the kernel doesn't have to handle them as special cases. >(I simplified (and fixed) one version of that code.) > > David > It's a fault in user space. I had a brain fart and managed to forget that RSP is technically a GPR and as such is not limited to the VA width of the machine.
