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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 5/15/24 22:05, Sean Christopherson wrote: >> Again thinking of the userspace memory analogy... Aren't there some VMs where >> the fast zap is faster? Like if you have guest with a small memslot that gets >> deleted all the time, you could want it to be zapped specifically. But for the >> giant memslot next to it, you might want to do the fast zap all thing. > > Yes. But... On the other hand, tearing down a giant memslot isn't really common. The main occurrence of memslots going away is 1) BIOS fiddling with low memory permissions; 2) PCI BARs. The former is only happening at boot and with small memslots, the latter can in principle involve large memslots but... just don't do it. Paolo