Re: [RFC 0/3] Put vdso in ramfs-like filesystem (vdsofs)

From: H. Peter Anvin
Date: Tue Sep 20 2016 - 20:33:08 EST


On 09/20/16 17:22, H. Peter Anvin wrote:
> The more I'm thinking about this, why don't we simply have these (the
> various possible vdsos as well as vvar) as actual files in sysfs instead
> of introducing a new filesystem? I don't believe sysfs actually has to
> be mounted in order for sysfs files to have an inode.
>
> It could also be in procfs, I guess, but sysfs probably makes more sense.
>
> I'm thinking something like:
>
> /sys/kernel/vdso/{i386,x86_64,x32,vvar}
>
> Not only would this let the container people and so on do weird things
> much easier, but it ought to eliminate a whole slew of special cases.
>

Even crazier idea: instead of a separate vvar file, have the vvar page
just be a part of these files (as a shared page)... I'm wondering if we
can even use load_elf_interp() since after all it is an ELF shared
library image...

-hpa