From mboxrd@z Thu Jan  1 00:00:00 1970
From: Florian Weimer <fweimer@redhat.com>
Subject: Re: Official Linux system wrapper library?
Date: Wed, 14 Nov 2018 12:40:44 +0100
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* Dave Martin:

> Fair points, though this is rather what I meant by "sane essentials".
> Because there are strict limits on what can be done in the vDSO, it may
> be more bloat-resistant and more conservatively maintained.
>
> This might provide a way to push some dumb compatibility kludge code
> that receives little ongoing maintenance outside the privilege wall,
> whereas it has to sit in the kernel proper today.
>
> In theory we could opt to advertise new syscalls only via vDSO entry
> points, and not maintain __NR_xxx values for them (which may or may
> not upset ptrace users.)  Anyway, I digress...

Is the vDSO available across all architectures?  (I don't think we use
it on all architectures in glibc.)

If not, a vDSO-based approach would merely lead to even more variance
between architectures, which can't be a good thing.

Thanks,
Florian