Re: [PATCH RESEND v4 23/23] KVM: x86: smm: preserve interrupt shadow in SMRAM

On 10/25/22 14:47, Maxim Levitsky wrote:

@@ -19,7 +19,8 @@ struct kvm_smram_state_32 { u32 reserved1[62]; u32 smbase; u32 smm_revision;

• u32 reserved2[5];

• u32 reserved2[4];
• u32 int_shadow; /* KVM extension */ u32 cr4; /* CR4 is not present in Intel/AMD SMRAM image */ u32 reserved3[5];

Of course the placement of KVM-specific fields is somewhat arbitrary, but based on sandpile.org data I would place it at 0xFF1A ("reserved", you have to search for 7F1Ah in the web page).

@@ -86,7 +87,7 @@ struct kvm_smram_state_64 { u64 io_restart_rsi; u64 io_restart_rdi; u32 io_restart_dword;

• u32 reserved1;

• u32 int_shadow; u8 io_inst_restart; u8 auto_hlt_restart; u8 reserved2[6];

Likewise, based on AMD BKDG I would place this at 0xFECB after the "NMI Mask" field (which unfortunately I learnt about only after "inventing" HF_SMM_INSIDE_NMI_MASK).

I can do the changes myself, but please ack.

Paolo