fix: Remove duplicate check for MAX_SUPPORT_VCPUS from restore path

This check already happens in `update_vm_config`, so no need to do it a
second time in `snapshot_state_sanity_check`.

Signed-off-by: Patrick Roy <[email protected]>

Author: roypat

src/vmm/src/persist.rs

@@ -32,7 +32,7 @@ use crate::resources::VmResources;
 use crate::snapshot::Snapshot;
 use crate::vmm_config::boot_source::BootSourceConfig;
 use crate::vmm_config::instance_info::InstanceInfo;
-use crate::vmm_config::machine_config::{MachineConfigUpdate, VmConfigError, MAX_SUPPORTED_VCPUS};
+use crate::vmm_config::machine_config::{MachineConfigUpdate, VmConfigError};
 use crate::vmm_config::snapshot::{
     CreateSnapshotParams, LoadSnapshotParams, MemBackendType, SnapshotType,
 };
@@ -329,8 +329,6 @@ pub fn validate_cpu_manufacturer_id(microvm_state: &MicrovmState) {
 /// Error type for [`snapshot_state_sanity_check`].
 #[derive(Debug, thiserror::Error, displaydoc::Display, PartialEq, Eq)]
 pub enum SnapShotStateSanityCheckError {
-    /// Invalid vCPU count.
-    InvalidVcpuCount,
     /// No memory region defined.
     NoMemory,
 }
@@ -339,13 +337,6 @@ pub enum SnapShotStateSanityCheckError {
 pub fn snapshot_state_sanity_check(
     microvm_state: &MicrovmState,
 ) -> Result<(), SnapShotStateSanityCheckError> {
-    // Check if the snapshot contains at least 1 vCPU state entry.
-    if microvm_state.vcpu_states.is_empty()
-        || microvm_state.vcpu_states.len() > MAX_SUPPORTED_VCPUS.into()
-    {
-        return Err(SnapShotStateSanityCheckError::InvalidVcpuCount);
-    }
-
     // Check if the snapshot contains at least 1 mem region.
     // Upper bound check will be done when creating guest memory by comparing against
     // KVM max supported value kvm_context.max_memslots().

src/vmm/tests/integration_tests.rs

@@ -305,26 +305,6 @@ fn test_snapshot_load_sanity_checks() {
             .vcpu_states
             .append(&mut microvm_state.vcpu_states.clone());
     }
-
-    // After this line we will have 33 vCPUs, FC max si 32.
-    microvm_state
-        .vcpu_states
-        .push(microvm_state.vcpu_states[0].clone());
-
-    // Validate sanity checks fail because there are too many vCPUs.
-    assert_eq!(
-        snapshot_state_sanity_check(&microvm_state),
-        Err(SnapShotStateSanityCheckError::InvalidVcpuCount)
-    );
-
-    // Remove all vCPUs states from microvm state.
-    microvm_state.vcpu_states.clear();
-
-    // Validate sanity checks fail because there is no vCPU in state.
-    assert_eq!(
-        snapshot_state_sanity_check(&microvm_state),
-        Err(SnapShotStateSanityCheckError::InvalidVcpuCount)
-    );
 }
 
 fn get_microvm_state_from_snapshot() -> MicrovmState {