On 4/12/24 5:07 PM, Andrew Cooper wrote:
On 12/04/2024 3:38 pm, Vaishali Thakkar wrote:
On 4/12/24 4:06 PM, Andrei Semenov wrote:
On 4/11/24 20:32, Andrew Cooper wrote:
On 10/04/2024 4:36 pm, Andrei Semenov wrote:
+ }
+
+ if (!(cpu_has_sme || cpu_has_sev))
+ return;
+
+ if (!smp_processor_id()) {
+ if (cpu_has_sev)
+ printk(XENLOG_INFO "SEV: ASID range [0x%x - 0x%x]\n",
+ min_sev_asid, max_sev_asid);
Why do we have a min as well as a max? Isn't min always 1?
In the case of SEV, it's not true. Some BIOS allow to set the
min_asid. So yeah Xen will also need to adapted for the same.
I've a WIP patch for allowing dynamic generation of asid in such
a case.
I also got an answer to this out of a contact of mine at AMD.
The ASID space is divided, 1->$N for SEV-ES/SNP guest, and $N->$M for
SEV guests.
It is a security issue to start a guest as ES/SNP, then "migrate" it to
being SEV-only, so the different types are tracked explicitly.
Aha, yeah that seems like a better explanation. Thanks for checking with
the AMD person.
~Andrew
