On Wed, 2021-06-23 at 11:39 +0200, Paolo Bonzini wrote: > On 23/06/21 09:44, Vitaly Kuznetsov wrote: > > - RFC: I'm not 100% sure my 'smart' idea to use currently-unused HSAVE area > > is that smart. Also, we don't even seem to check that L1 set it up upon > > nested VMRUN so hypervisors which don't do that may remain broken. A very > > much needed selftest is also missing. > > It's certainly a bit weird, but I guess it counts as smart too. It > needs a few more comments, but I think it's a good solution. > > One could delay the backwards memcpy until vmexit time, but that would > require a new flag so it's not worth it for what is a pretty rare and > already expensive case. > > Paolo > I wonder what would happen if SMM entry is triggered by L1 (say with ICR), on a VCPU which is in L2. Such exit should go straight to L1 SMM mode. I will very very soon, maybe even today start testing SMM with my migration tests and such. I hope I will find more bugs in this area. Thanks for fixing this issue! Best regards, Maxim Levitsky
