The priority range was changed several years ago, but the
userland-reported limits were just forgotten :skeleyak:. Move the thread
priority constants into an API header so that userland can use it
properly.
The syscalls are renamed as they no longer reflect the exact POSIX
functionality. They can now handle setting/getting scheduler parameters
for both threads and processes.
SPDX License Identifiers are a more compact / standardized
way of representing file license information.
See: https://spdx.dev/resources/use/#identifiers
This was done with the `ambr` search and replace tool.
ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *
This achieves two things:
- Programs can now intentionally perform arbitrary syscalls by calling
syscall(). This allows us to work on things like syscall fuzzing.
- It restricts the ability of userspace to make syscalls to a single
4KB page of code. In order to call the kernel directly, an attacker
must now locate this page and call through it.
