[CRIU] [PATCH 0/2] files: Add ability to skip certain files for size check

[Cyrill Gorcunov]

On Fri, Mar 24, 2017 at 12:43:49PM +0300, Pavel Emelyanov wrote:
> >>
> >> I don't like the idea of such an option :( I'd rather agree on
> >> some quirk inside the criu code to skip files of that kind.
> > 
> > The option is just fine. Otherwise we leave customers without
> > ability to restore applications which use acct() syscall. 
> 
> Come on, for Virtuozzo case, you can put any hack into vzkernel and
> keep tiny patch in criu .spec file ;)

You must be kiddin, right? Vz case already have a quirk and I
don't like it -- it's not firmware which is immutable in most
case (for which kernel has to carry hackinsh fixups). The
acct() syscall is pretty valid and any program can use it.

For our containers we know which quirks to add and can
hardcode it. But how to be with the rest of the users?
They really have to be able to say criu somehow -- hey,
this file is known to be changed after the stop, please
don't check for its size on restore.

> > How mayn quirks we will have to keep?
> 
> With this option, you'll have to maintain the same set of quirks anyway.
> But in another (hell knows which) place.

In turn, they _may_ be dynamic with the option. And
if someone come with such error because he can't restore
container we can tell him -- just pass this option
on restore procedure.