Naveen N Rao <nav...@kernel.org> writes: > Hi Markus, > > On Fri, Sep 12, 2025 at 01:20:43PM +0200, Markus Armbruster wrote: >> "Naveen N Rao (AMD)" <nav...@kernel.org> writes: >> >> > Add support for enabling debug-swap VMSA SEV feature in SEV-ES and >> > SEV-SNP guests through a new "debug-swap" boolean property on SEV guest >> > objects. Though the boolean property is available for plain SEV guests, >> > check_sev_features() will reject setting this for plain SEV guests. >> >> Let's see whether I understand... >> >> It's a property of sev-guest and sev-snp-guest objects. These are the >> "SEV guest objects". >> >> I guess a sev-snp-guest object implies it's a SEV-SNP guest, and setting >> @debug-swap on such an object just works. >> >> With a sev-guest object, it's either a "plain SEV guest" or a "SEV-ES" >> guest. >> >> If it's the latter, setting @debug-swap just works. >> >> If it's the former, and you set @debug-swap to true, then KVM >> accelerator initialization will fail later on. This might trigger >> fallback to TCG. >> >> Am I confused? > > You're spot on, except that in the last case above (plain old SEV > guest), qemu throws an error: > qemu-system-x86_64: check_sev_features: SEV features require either > SEV-ES or SEV-SNP to be enabled
Okay. Can you (or anyone) explain to me why SEV-SNP gets its own object type, but SEV-ES does not? [...]
