Revert "x86/mm/ident_map: Use gbpages only where full GB page should be mapped."

commit c567f294 upstream.

This reverts commit d794734c.

While the original change tries to fix a bug, it also unintentionally broke
existing systems, see the regressions reported at:

  https://lore.kernel.org/all/3a1b9909-45ac-4f97-ad68-d16ef1ce99db@pavinjoseph.com/

Since d794734c was also marked for -stable, let's back it out before
causing more damage.

Note that due to another upstream change the revert was not 100% automatic:

  0a845e0f

 mm/treewide: replace pud_large() with pud_leaf()

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: <stable@vger.kernel.org>
Cc: Russ Anderson <rja@hpe.com>
Cc: Steve Wahl <steve.wahl@hpe.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/all/3a1b9909-45ac-4f97-ad68-d16ef1ce99db@pavinjoseph.com/
Fixes: d794734c

 ("x86/mm/ident_map: Use gbpages only where full GB page should be mapped.")
Signed-off-by: Steve Wahl <steve.wahl@hpe.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>