Re: [PATCH 0/2] vmstate-static-checker: Fix VMS_ARRAY comparisons

[Juan Quintela]

Peter Xu <peterx@redhat.com> wrote:
> I'm doing some machine type checks to make sure nothing breaks for
> 7.2<->8.0.  Along the way I found one false negative report on e1000e using
> the static checker, turns out to be an issue in the checker itself.
>
> The problem is the checker doesn't take VMS_ARRAY into account when
> comparing with UNUSED, hence the total size is wrongly calculated.
>
> Fix that first in qemu by start dumping size of array as "num", then teach
> the checker for that.
>
> NOTE: the patchset will change both behaviors for either -dump-vmstate on
> QEMU or the checker, however both patches will be compatible even with old
> QEMU dumps or even old vmstate-checker script.  That's not extremely
> important, IMHO, but still worth mentioning.
>
> Thanks,
>
> Peter Xu (2):
>   migration/vmstate-dump: Dump array size too as "num"
>   vmstate-static-checker: Recognize "num" field
>
>  migration/savevm.c                |  3 +++
>  scripts/vmstate-static-checker.py | 13 ++++++++++---
>  2 files changed, 13 insertions(+), 3 deletions(-)

Hi

once that you are working with the static checker.

Could we just run two checks in make check:

- qemu-<whatever> -M <previous-version> against the one from previous
  version, and see that they match.
- qemu-<whatever> -M <latests> against the one from previous version
  And we save the diffs each time that we add something incompatible and
  fix it on source.

I will start with x86_64.  And once that we have it running, the other
architectures that care about version compatibility can add to it.

What do you think?

Later, Juan.