On Thu, May 02, 2019 at 06:21:33PM +0200, Peter Zijlstra wrote: > Much thanks to Joerg Roedel for talking entry_32.S with me. > > TL;DR, on x86_32 kernel->kernel IRET frames are only 3 entries and do > not include ESP/SS, so not only wasn't regs->sp setup, if you changed it > it wouldn't be effective and corrupt random stack state. Also, i386 is bloody insane...
