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    SubjectRe: [PATCH 000/109] remove in-kernel calls to syscalls
    On Thu, Mar 29, 2018 at 07:20:27AM -0700, Matthew Wilcox wrote:
    > 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()?

    Once the patches which modify the syscall calling convention are merged,
    it won't compile on 64-bit x86, but bark loudly. That should frighten anyone.
    Meow.

    Thanks,
    Dominik

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