fix(vmm): Bump snapshot version

To support the snapshot feature for Intel AMX, we changed to use
`Xsave` struct instead of `kvm_xsave` struct. We should have bumped the
snapshot version.

Fixes: 803140d ("feat(vmm): Use structs and methods for KVM_CAP_XSAVE2")
Signed-off-by: Takahiro Itazuri <[email protected]>

Author: zulinx86

CHANGELOG.md

@@ -16,7 +16,9 @@ and this project adheres to
   Linux kernels newer than 5.0 compiled with `CONFIG_PVH=y` set this ELF Note,
   as do FreeBSD kernels.
 - [#5065](https://github.com/firecracker-microvm/firecracker/pull/5065) Added
-  support for Intel AMX (Advanced Matrix Extensions).
+  support for Intel AMX (Advanced Matrix Extensions). To be able to take and
+  restore a snapshot of Intel AMX state, `Xsave` is used instead of `kvm_xsave`,
+  so users need to regenerate snapshots.
 - [#4731](https://github.com/firecracker-microvm/firecracker/pull/4731): Added
   support for modifying the host TAP device name during snapshot restore.
 

src/vmm/src/persist.rs

@@ -148,7 +148,7 @@ pub enum CreateSnapshotError {
 }
 
 /// Snapshot version
-pub const SNAPSHOT_VERSION: Version = Version::new(5, 0, 0);
+pub const SNAPSHOT_VERSION: Version = Version::new(6, 0, 0);
 
 /// Creates a Microvm snapshot.
 pub fn create_snapshot(