Merge commit '7ed6fb9b' into x86/espfix

Merge in Linus' tree with:

fa81511b x86-64, modify_ldt: Make support for 16-bit segments a runtime option

... reverted, to avoid a conflict.  This commit is no longer necessary
with the proper fix in place.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>