snp_guest_msg_hdr
struct snp_guest_msg_hdr *req_msg_hdr = &req_msg->hdr;
struct snp_guest_msg_hdr *resp_msg_hdr = &resp_msg->hdr;
struct snp_guest_msg_hdr *hdr = &msg->hdr;
struct snp_guest_msg_hdr hdr;
u8 payload[PAGE_SIZE - sizeof(struct snp_guest_msg_hdr)];
if (kvm_read_guest(kvm, req_gpa + offsetof(struct snp_guest_msg_hdr, msg_type),