[CRIU] [PATCH 2/4] Make vDSO warning behave as such

[Cyrill Gorcunov]

On Fri, Jul 18, 2014 at 10:12:41AM -0400, Christopher Covington wrote:
> >
> > Good to know! The problem is that I'm reworking vdso code (because there a change
> > coming from the kernel side soon which will make code a bit more complicated) so
> > if current x86 code works for arm then probably we could copy it into arm and
> > then simplify removing all unneded things (as far as I remember on arm vdso
> > code was rather a stub doing nothing, no?).
> 
> What change are you talking about?

vDSO and VVAR zones are reviesed in latest linux-next which cause criu to
fail. I've finished the rework and testing/reviewing changes at the moment.
Hopefully will post new patches soon so you see which changes I'm talking
about.

> 
> The 32-bit arm code was a stub but those VDSO patches may get merged soon.
> aarch64 did not use the stub.
> 
> There are some aarch64 VDSO changes coming up:
> 
> http://git.kernel.org/cgit/linux/kernel/git/arm64/linux.git/commit/?id=8715493852783358ef8656a0054a14bf822509cf
> http://git.kernel.org/cgit/linux/kernel/git/arm64/linux.git/commit/?id=2fea7f6c98f5957e539eb8aa0ce849729b900342
> http://git.kernel.org/cgit/linux/kernel/git/arm64/linux.git/commit/?id=601255ae3c98fdeeee3a8bb4696425e4f868b4f1
> http://git.kernel.org/cgit/linux/kernel/git/arm64/linux.git/commit/?id=ad789ba5f7086138461420d2156478d33fb61077
> 
> As far as I can tell the main impact is that the relative order of vdso and
> vvar is reversed (I believe this is also the case for x86_32). For dumping I
> can trivially extend a sanity check. For restoring my progress has been
> slower. My first instinct is to break the vdso and vvar handling apart, but do
> you have any different suggestions?

Well. My strong opinion is that arch code must not be shared at all.
Christopher, gimme some time to finish my current patch queue and
I believe we will find a common groud for vdso and work out a strategy
on how to handle it over all archs, ok?