UefiCpuPkg/CpuDxe: implement non-stop mode for uefi
Same as SMM profile feature, a special #PF is used to set page attribute
to 'present' and a special #DB handler to reset it back to 'not-present',
right after the instruction causing #PF got executed.
Since the new #PF handler won't enter into dead-loop, the instruction
which caused the #PF will get chance to re-execute with accessible pages.
The exception message will still be printed out on debug console so that
the developer/QA can find that there's potential heap overflow or null
pointer access occurred.
Cc: Eric Dong <eric.dong@intel.com> Cc: Laszlo Ersek <lersek@redhat.com> Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Jian J Wang <jian.j.wang@intel.com> Reviewed-by: Eric Dong <eric.dong@intel.com> Acked-by: Laszlo Ersek <lersek@redhat.com>