On 26.02.20 16:11, Janosch Frank wrote: > On 2/26/20 3:59 PM, David Hildenbrand wrote: >> On 26.02.20 13:20, Janosch Frank wrote: >>> Ballooning in protected VMs can only be done when the guest shares the >>> pages it gives to the host. Hence, until we have a solution for this >>> in the guest kernel, we inhibit ballooning when switching into >>> protected mode and reverse that once we move out of it. >> >> I don't understand what you mean here, sorry. zapping a page will mean >> that a fresh one will be faulted in when accessed. And AFAIK, that means >> it will be encrypted again when needed. > > Yes, as soon as the host alters non-shared memory we'll run into > integrity issues. > > > I've been talking to Halil after I sent this out and it looks like we'll > rather try to automatically enable the IOMMU for all devices when > switching into protected mode. He said that if the IOMMU is set the > balloon code will do an early exit on feature negotiation. I think we should fence the balloon here nevertheless, so the patch in itself is probably fine.
- Re: [PATCH v6] s390x: Rena... David Hildenbrand
- Re: [PATCH v6] s390x: Rena... Cornelia Huck
- [PATCH v5 07/18] s390x: protvirt: Inhibit balloon wh... Janosch Frank
- Re: [PATCH v5 07/18] s390x: protvirt: Inhibit b... David Hildenbrand
- Re: [PATCH v5 07/18] s390x: protvirt: Inhib... Christian Borntraeger
- Re: [PATCH v5 07/18] s390x: protvirt: I... David Hildenbrand
- Re: [PATCH v5 07/18] s390x: protvir... Janosch Frank
- Re: [PATCH v5 07/18] s390x: pr... David Hildenbrand
- Re: [PATCH v5 07/18] s390x: pr... Cornelia Huck
- Re: [PATCH v5 07/18] s390x: protvirt: Inhib... Janosch Frank
- Re: [PATCH v5 07/18] s390x: protvirt: I... Christian Borntraeger
- Re: [PATCH v5 07/18] s390x: protvir... David Hildenbrand
- Re: [PATCH v5 07/18] s390x: protvirt: I... Halil Pasic
- [PATCH v5 02/18] Sync pv Janosch Frank
- [PATCH v5 05/18] s390x: protvirt: Add migration bloc... Janosch Frank
- Re: [PATCH v5 05/18] s390x: protvirt: Add migra... Christian Borntraeger
- Re: [PATCH v5 05/18] s390x: protvirt: Add m... Janosch Frank
- [PATCH v5 08/18] s390x: protvirt: KVM intercept chan... Janosch Frank
- [PATCH v5 14/18] s390x: protvirt: Disable address ch... Janosch Frank
- [PATCH v5 04/18] s390x: protvirt: Support unpack fac... Janosch Frank
- [PATCH v5 10/18] s390x: protvirt: Move STSI data ove... Janosch Frank