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Date: Thu, 29 Mar 2018 07:20:27 -0700
From: Matthew Wilcox <willy@infradead.org>
To: Dominik Brodowski <linux@dominikbrodowski.net>
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Subject: Re: [PATCH 000/109] remove in-kernel calls to syscalls
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On Thu, Mar 29, 2018 at 01:22:37PM +0200, Dominik Brodowski wrote:
> At least on 64-bit x86, it will likely be a hard requirement from v4.17
> onwards to not call system call functions in the kernel: It is better to
> use use a different calling convention for system calls there, where 
> struct pt_regs is decoded on-the-fly in a syscall wrapper which then hands
> processing over to the actual syscall function. This means that only those
> parameters which are actually needed for a specific syscall are passed on
> during syscall entry, instead of filling in six CPU registers with random
> user space content all the time (which may cause serious trouble down the
> call chain).[*]

How do we stop new ones from springing up?  Some kind of linker trick
like was used to, er, "dissuade" people from using gets()?