vmm: arch: Make phys_bits functionality use CPU vendor API

Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>

arch/src/aarch64/mod.rs

@@ -198,11 +198,8 @@ pub fn initramfs_load_addr(
     }
 }
 
-pub fn get_host_cpu_phys_bits() -> u8 {
+pub fn get_host_cpu_phys_bits(hypervisor: &Arc<dyn hypervisor::Hypervisor>) -> u8 {
-    // A dummy hypervisor created only for querying the host IPA size and will
+    let host_cpu_phys_bits = hypervisor.get_host_ipa_limit().try_into().unwrap();
-    // be freed after the query.
-    let hv = hypervisor::new().unwrap();
-    let host_cpu_phys_bits = hv.get_host_ipa_limit().try_into().unwrap();
     if host_cpu_phys_bits == 0 {
         // Host kernel does not support `get_host_ipa_limit`,
         // we return the default value 40 here.

arch/src/x86_64/mod.rs

@@ -16,7 +16,7 @@ use crate::GuestMemoryMmap;
 use crate::InitramfsConfig;
 use crate::RegionType;
 use hypervisor::arch::x86::{CpuIdEntry, CPUID_FLAG_VALID_INDEX};
-use hypervisor::{HypervisorCpuError, HypervisorError};
+use hypervisor::{CpuVendor, HypervisorCpuError, HypervisorError};
 use linux_loader::loader::bootparam::boot_params;
 use linux_loader::loader::elf::start_info::{
     hvm_memmap_table_entry, hvm_modlist_entry, hvm_start_info,
@@ -1078,7 +1078,7 @@ pub fn initramfs_load_addr(
     Ok(aligned_addr)
 }
 
-pub fn get_host_cpu_phys_bits() -> u8 {
+pub fn get_host_cpu_phys_bits(hypervisor: &Arc<dyn hypervisor::Hypervisor>) -> u8 {
     // SAFETY: call cpuid with valid leaves
     unsafe {
         let leaf = x86_64::__cpuid(0x8000_0000);
@@ -1087,9 +1087,7 @@ pub fn get_host_cpu_phys_bits() -> u8 {
         // Some physical address bits may become reserved when the feature is enabled.
         // See AMD64 Architecture Programmer's Manual Volume 2, Section 7.10.1
         let reduced = if leaf.eax >= 0x8000_001f
-            && leaf.ebx == 0x6874_7541    // Vendor ID: AuthenticAMD
+            && matches!(hypervisor.get_cpu_vendor(), CpuVendor::AMD)
-            && leaf.ecx == 0x444d_4163
-            && leaf.edx == 0x6974_6e65
             && x86_64::__cpuid(0x8000_001f).eax & 0x1 != 0
         {
             (x86_64::__cpuid(0x8000_001f).ebx >> 6) & 0x3f

vmm/src/cpu.rs

@@ -716,7 +716,7 @@ impl CpuManager {
         );
 
         self.cpuid = {
-            let phys_bits = physical_bits(self.config.max_phys_bits);
+            let phys_bits = physical_bits(hypervisor, self.config.max_phys_bits);
             arch::generate_common_cpuid(
                 hypervisor,
                 topology,

vmm/src/lib.rs

@@ -1219,7 +1219,8 @@ impl Vmm {
             ))
         })?;
 
-        let phys_bits = vm::physical_bits(config.lock().unwrap().cpus.max_phys_bits);
+        let phys_bits =
+            vm::physical_bits(&self.hypervisor, config.lock().unwrap().cpus.max_phys_bits);
 
         let memory_manager = MemoryManager::new(
             vm,
@@ -1535,7 +1536,8 @@ impl Vmm {
         let vm_config = vm.get_config();
         #[cfg(all(feature = "kvm", target_arch = "x86_64"))]
         let common_cpuid = {
-            let phys_bits = vm::physical_bits(vm_config.lock().unwrap().cpus.max_phys_bits);
+            let phys_bits =
+                vm::physical_bits(&hypervisor, vm_config.lock().unwrap().cpus.max_phys_bits);
             arch::generate_common_cpuid(
                 &hypervisor,
                 None,
@@ -1725,7 +1727,7 @@ impl Vmm {
         let dest_cpuid = &{
             let vm_config = &src_vm_config.lock().unwrap();
 
-            let phys_bits = vm::physical_bits(vm_config.cpus.max_phys_bits);
+            let phys_bits = vm::physical_bits(&self.hypervisor, vm_config.cpus.max_phys_bits);
             arch::generate_common_cpuid(
                 &self.hypervisor.clone(),
                 None,

vmm/src/vm.rs

@@ -417,8 +417,8 @@ impl VmOps for VmOpsHandler {
     }
 }
 
-pub fn physical_bits(max_phys_bits: u8) -> u8 {
+pub fn physical_bits(hypervisor: &Arc<dyn hypervisor::Hypervisor>, max_phys_bits: u8) -> u8 {
-    let host_phys_bits = get_host_cpu_phys_bits();
+    let host_phys_bits = get_host_cpu_phys_bits(hypervisor);
 
     cmp::min(host_phys_bits, max_phys_bits)
 }
@@ -762,7 +762,7 @@ impl Vm {
             tdx_enabled,
         )?;
 
-        let phys_bits = physical_bits(vm_config.lock().unwrap().cpus.max_phys_bits);
+        let phys_bits = physical_bits(&hypervisor, vm_config.lock().unwrap().cpus.max_phys_bits);
 
         let memory_manager = if let Some(snapshot) =
             snapshot_from_id(snapshot.as_ref(), MEMORY_MANAGER_SNAPSHOT_ID)
@@ -2413,7 +2413,10 @@ impl Snapshottable for Vm {
 
         #[cfg(all(feature = "kvm", target_arch = "x86_64"))]
         let common_cpuid = {
-            let phys_bits = physical_bits(self.config.lock().unwrap().cpus.max_phys_bits);
+            let phys_bits = physical_bits(
+                &self.hypervisor,
+                self.config.lock().unwrap().cpus.max_phys_bits,
+            );
             arch::generate_common_cpuid(
                 &self.hypervisor,
                 None,