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by 10000truths 1283 days ago
Lack of syscall stability isn’t a showstopper, it just means that the functions invoking the syscall need to be versioned according to uname(). The uname() call itself can be done via direct syscall if you’re confident that its ABI won’t change; or, if you want to be extra sure, you can use the libc wrapper for uname() and then munmap() the C runtime to replace it with whatever. Either way requires the maintainer to be proactive with implementing code paths for upstream upcoming kernel versions before they are mainlined.

OpenBSD will make the above approach impossible, because with mimmutable(), libc will not be unmappable.
1 comments
saagarjha 1283 days ago
> The uname() call itself can be done via direct syscall if you’re confident that its ABI won’t change; or, if you want to be extra sure, you can use the libc wrapper for uname() and then munmap() the C runtime to replace it with whatever.

I would ask why you would want to do this.

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