Re: [PATCH] vhost/migration: Fix incorrect size used in inflight->addr in VMSD

Peter Xu <[email protected]> writes:

> On Wed, Jul 29, 2026 at 11:27:44AM -0300, Fabiano Rosas wrote:
>> Hm, but isn't it better to have a global cap anyway? So we don't need
>> every device code to change with similar checks.
>> 
>> > If we go this route, I'd rather merge Michael's version to support u64,
>> > even if we don't need a u64 size.  But I really don't want to introduce yet
>> > another VMS flag just for this... we'll have no real use if we have noticed
>> > this problem when the vhost inflight patch was reviewed.  It will be a
>> > uint32_t or int32_t already.  I just can't come up with some users need
>> > size >2G.
>> >
>> 
>> I agree with making all u64. I think we can actually remove all the
>> extra VMS_VARRAY_* and VBUFFER_* flags and instead doa single type-check
>> of "int <= 64bit". Give me a couple of hours and I will post an RFC.
>
> I confess I don't yet get what is the global cap you mentioned.. but sure,
> I'll wait and read the RFC first.

I was thinking the vmstate code could define a limit to the size (of
anything) and always enforce it. The device code can then use some
custom macros (not yet existent) to limit even further.