On Mon, 2022-11-14 at 13:32 +0530, Santosh Shukla wrote: > > > On 10/27/2022 2:08 PM, Santosh Shukla wrote: > > VNMI Spec is at [1]. > > > > Change History: > > > > v5 (6.1-rc2) > > 01,02,06 - Renamed s/X86_FEATURE_V_NMI/X86_FEATURE_AMD_VNMI (Jim Mattson) > > > > Gentle reminder. > > Thanks, > Santosh > I started reviewing it today and I think there are still few issues, and the biggest one is that if a NMI arrives while vNMI injection is pending, current code just drops such NMI. We had a discussion about this, like forcing immeditate vm exit in this case and such but I have a simplier idea: In this case we can just open the NMI window in the good old way by intercepting IRET, STGI, and or RSM (which is intercepted anyway), and only if we already *just* intercepted IRET, only then just drop the new NMI instead of single stepping over it based on reasoning that its 3rd NMI (one is almost done the servicing (its IRET is executing), one is pending injection, and we want to inject another one. Does this sound good to you? It won't work for SEV-ES as it looks like it doesn't intercept IRET, but it might be a reasonable tradeof for SEV-ES guests to accept that we can't inject a NMI if one is already pending injection. Best regards, Maxim Levitsky
