On Wed, Jan 17, 2018 at 05:57:53AM -0800, Brian Gerst wrote: > On Wed, Jan 17, 2018 at 1:24 AM, Joerg Roedel <joro@xxxxxxxxxx> wrote: > > I have no real idea on how to switch back to the entry stack without > > access to per_cpu variables. I also can't access the cpu_entry_area for > > the cpu yet, because for that we need to be on the entry stack already. > > Switch to the trampoline stack before loading user segments. That requires to copy most of pt_regs from task- to trampoline-stack, not sure if that is faster than temporily restoring kernel %fs. Joerg -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
