On 17/01/18 09:02, Joerg Roedel wrote: > Hi Boris, > > thanks for testing this :) > > On Tue, Jan 16, 2018 at 09:47:06PM -0500, Boris Ostrovsky wrote: >> On 01/16/2018 11:36 AM, Joerg Roedel wrote: >>> +.macro SWITCH_TO_KERNEL_STACK nr_regs=0 check_user=0 >> >> This (and next patch's SWITCH_TO_ENTRY_STACK) need X86_FEATURE_PTI check. >> >> With those macros fixed I was able to boot 32-bit Xen PV guest. > Hmm, on bare metal the stack switch happens regardless of the > X86_FEATURE_PTI feature being set, because we always program tss.sp0 > with the systenter stack. How is the kernel entry stack setup on xen-pv? > I think something is missing there instead. There is one single stack registered with Xen, on which you get a normal exception frame in all cases, even via the registered (virtual) syscall/sysenter/failsafe handlers. ~Andrew -- 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>
