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Subject: Re: [RFC 0/3] Put vdso in ramfs-like filesystem (vdsofs)
To: Dmitry Safonov <0x7f454c46@gmail.com>
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Cc: Dmitry Safonov <dsafonov@virtuozzo.com>, linux-kernel@vger.kernel.org,
        Ingo Molnar <mingo@redhat.com>, Andy Lutomirski <luto@amacapital.net>,
        Thomas Gleixner <tglx@linutronix.de>, X86 ML <x86@kernel.org>,
        Oleg Nesterov <oleg@redhat.com>, Steven Rostedt <rostedt@goodmis.org>,
        viro@zeniv.linux.org.uk
From: "H. Peter Anvin" <hpa@zytor.com>
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Date: Tue, 20 Sep 2016 17:32:54 -0700
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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