Enable vsyscall emulation

modulename: vsyscall_64.ko


Linux Kernel Configuration
└─>Processor type and features
└─>Enable vsyscall emulation
In linux kernel since version 3.10 (release Date: 2013-06-30)  
This enables emulation of the legacy vsyscall page. Disabling
it is roughly equivalent to booting with vsyscall=none, except
that it will also disable the helpful warning if a program
tries to use a vsyscall. With this option set to N, offending
programs will just segfault, citing addresses of the form

This option is required by many programs built before 2013, and
care should be used even with newer programs if set to N.

Disabling this option saves about 7K of kernel size and
possibly 4K of additional runtime pagetable memory.

source code: