[CRIU] [PATCH] Add checkpoint/restore for /proc/pid/exe symlink

[Cyrill Gorcunov]

On Mon, Feb 06, 2012 at 08:29:53PM +0400, Cyrill Gorcunov wrote:
> > 
> > We do not migrate unlinked files yet? Or we don't even check, that
> > this file is unlinked?
> 
> For this particular case -- the presence of file exe point to is
> tested by the kernel itself, ie we rather don't care which path
> is passed. Is that what you mean in question?

If you mean the files in general -- then we're trying to re-open
all files at restore (we've saved the paths in image file) and if
it fails -- then restore will simply stop continue.

> > Why do we need change this symlink at all?
> 
> Otherwise we will have the link to crtools here, since it's
> crtools who is executed and forked then. The potential problem
> here is that the kernel have no idea about Elf structure once
> elf loaded and running, the kernel operates with VMAs and I
> fear it's possible that this exe link might be used by loader
> on lazy load of .so files *BUT* I didn't checked if it's true.
> 
> And after all, Stas, it was you how were complaining about
> wrong /proc/pid/exe after restore? :)

Another thing is that we don't know how the dumpee may use this
link somewhere else in code, so better to be on safe side and try
to recreate an environment the dumpee had 1:1.

	Cyrill