diff --git a/src/main.rs b/src/main.rs
index d02c94f6d..69ea90c6d 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -97,7 +97,8 @@ fn create_app<'a, 'b>(
                 .long("cpus")
                 .help(
                     "boot=<boot_vcpus>,max=<max_vcpus>,\
-                    topology=<threads_per_core>:<cores_per_die>:<dies_per_package>:<packages>,kvm_hyperv=on|off",
+                    topology=<threads_per_core>:<cores_per_die>:<dies_per_package>:<packages>,\
+                    kvm_hyperv=on|off,max_phys_bits=<maximum_number_of_physical_bits>",
                 )
                 .default_value(&default_vcpus)
                 .group("vm-config"),
@@ -133,8 +134,10 @@ fn create_app<'a, 'b>(
         .arg(
             Arg::with_name("kernel")
                 .long("kernel")
-                .help("Path to loaded kernel. This may be a kernel or firmware that supports a PVH \
-                entry point, a vmlinux ELF file or a Linux bzImage or achitecture equivalent")
+                .help(
+                    "Path to loaded kernel. This may be a kernel or firmware that supports a PVH \
+                entry point, a vmlinux ELF file or a Linux bzImage or achitecture equivalent",
+                )
                 .takes_value(true)
                 .group("vm-config"),
         )
@@ -545,6 +548,7 @@ mod unit_tests {
                     max_vcpus: 1,
                     topology: None,
                     kvm_hyperv: false,
+                    max_phys_bits: None,
                 },
                 memory: MemoryConfig {
                     size: 536_870_912,
diff --git a/vmm/src/api/openapi/cloud-hypervisor.yaml b/vmm/src/api/openapi/cloud-hypervisor.yaml
index f7cbc1165..e609adc0a 100644
--- a/vmm/src/api/openapi/cloud-hypervisor.yaml
+++ b/vmm/src/api/openapi/cloud-hypervisor.yaml
@@ -469,6 +469,8 @@ components:
           type: integer
         topology:
             $ref: '#/components/schemas/CpuTopology'
+        max_phys_bits:
+          type: integer
 
     MemoryZoneConfig:
       required:
diff --git a/vmm/src/config.rs b/vmm/src/config.rs
index 646e62263..bc5a5d3ef 100644
--- a/vmm/src/config.rs
+++ b/vmm/src/config.rs
@@ -320,6 +320,8 @@ pub struct CpusConfig {
     pub topology: Option<CpuTopology>,
     #[serde(default)]
     pub kvm_hyperv: bool,
+    #[serde(default)]
+    pub max_phys_bits: Option<u8>,
 }
 
 impl CpusConfig {
@@ -329,7 +331,8 @@ impl CpusConfig {
             .add("boot")
             .add("max")
             .add("topology")
-            .add("kvm_hyperv");
+            .add("kvm_hyperv")
+            .add("max_phys_bits");
         parser.parse(cpus).map_err(Error::ParseCpus)?;
 
         let boot_vcpus: u8 = parser
@@ -346,12 +349,16 @@ impl CpusConfig {
             .map_err(Error::ParseCpus)?
             .unwrap_or(Toggle(false))
             .0;
+        let max_phys_bits = parser
+            .convert::<u8>("max_phys_bits")
+            .map_err(Error::ParseCpus)?;
 
         Ok(CpusConfig {
             boot_vcpus,
             max_vcpus,
             topology,
             kvm_hyperv,
+            max_phys_bits,
         })
     }
 }
@@ -363,6 +370,7 @@ impl Default for CpusConfig {
             max_vcpus: DEFAULT_VCPUS,
             topology: None,
             kvm_hyperv: false,
+            max_phys_bits: None,
         }
     }
 }