We now switch to the kernel stack when a machine check interrupts
during user mode.  This means that we can perform recovery actions
in the tail of do_machine_check()
Acked-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NAndy Lutomirski <luto@amacapital.net>