From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [RFC 21/22] x86/module: Add support for mcmodel large and PLTs
Date: Tue, 18 Jul 2017 18:35:05 -0700
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On 07/18/17 15:33, Thomas Garnier wrote:
> With PIE support and KASLR extended range, the modules may be further
> away from the kernel than before breaking mcmodel=kernel expectations.
> 
> Add an option to build modules with mcmodel=large. The modules generated
> code will make no assumptions on placement in memory.
> 
> Despite this option, modules still expect kernel functions to be within
> 2G and generate relative calls. To solve this issue, the PLT arm64 code
> was adapted for x86_64. When a relative relocation go outside its range,
> a dynamic PLT entry is used to correctly jump to the destination.

Why large as opposed to medium or medium-PIC?

	-hpa