On Wed, May 14, 2025 at 11:26:05AM +0200, David Hildenbrand wrote: > On 14.05.25 11:12, Igor Mammedov wrote: > > On Tue, 13 May 2025 15:12:11 +0200 > > David Hildenbrand <da...@redhat.com> wrote: > > > > > On 13.05.25 14:13, Igor Mammedov wrote: > > > > On Mon, 3 Mar 2025 13:02:17 -0500 > > > > yuanminghao <yuanm...@chinatelecom.cn> wrote: > > > > > > > Global used_memslots or used_shared_memslots is updated to 0 > > > > > > > unexpectly > > > > > > > > > > > > it shouldn't be 0 in practice, as it comes from number of RAM > > > > > > regions VM has. > > > > > > It's likely a bug somewhere else. > > > > > > > > I haven't touched this code for a long time, but I'd say if we consider > > > > multiple > > > > devices, we shouldn't do following: > > > > > > > > static void vhost_commit(MemoryListener *listener) > > > > ... > > > > if (dev->vhost_ops->vhost_backend_no_private_memslots && > > > > dev->vhost_ops->vhost_backend_no_private_memslots(dev)) { > > > > used_shared_memslots = dev->mem->nregions; > > > > } else { > > > > used_memslots = dev->mem->nregions; > > > > } > > > > > > > > where value dev->mem->nregions gets is well hidden/obscured > > > > and hard to trace where tail ends => fragile. > > > > > > > > CCing David (accidental victim) who rewrote this part the last time, > > > > perhaps he can suggest a better way to fix the issue. > > > > > > I think the original idea is that all devices (of on type: private vs. > > > non-private memslots) have the same number of memslots. > > > > > > This avoids having to loop over all devices to figure out the number of > > > memslots. > > > > > > ... but in vhost_get_free_memslots() we already loop over all devices. > > > > > > The check in vhost_dev_init() needs to be taken care of. > > > > > > So maybe we can get rid of both variables completely? > > > > looks reasonable to me, (instead of current state which is > > juggling with dev->mem->nregions that can become 0 on unplug > > as it was reported). > > > > David, > > do you have time to fix it? > > I can try, but I was wondering/hoping whether Yuanminghao could take a look > at that? I can provide guidance if necessary.
Guys? > -- > Cheers, > > David / dhildenb