virt_mshv: invoke HvScrubPartition during reset

vmm_core/virt_mshv/src/aarch64/mod.rs

@@ -266,6 +266,7 @@ impl virt::ResetPartition for MshvPartition {
     type Error = Error;
 
     fn reset(&self) -> Result<(), Error> {
+        self.inner.scrub_partition()?;
         self.inner.freeze_time()?;
         Ok(())
     }

vmm_core/virt_mshv/src/lib.rs

@@ -312,6 +312,19 @@ impl MshvPartitionInner {
         &self.vps[vp_index.index() as usize]
     }
 
+    fn scrub_partition(&self) -> Result<(), Error> {
+        const HVCALL_SCRUB_PARTITION: libc::c_ulong = 0x008d;
+
+        // SAFETY: `vmfd` is a valid MSHV partition fd. The private MSHV ABI
+        // exposes HvCallScrubPartition directly as an argument-less ioctl.
+        let ret = unsafe { libc::ioctl(self.vmfd.as_raw_fd(), HVCALL_SCRUB_PARTITION) };
+        if ret < 0 {
+            return Err(ErrorInner::ScrubPartition(io::Error::last_os_error()).into());
+        }
+
+        Ok(())
+    }
+
     /// Freezes partition time. Time will remain frozen until [`thaw_time`] is
     /// called (typically on the first VP run after reset).
     fn freeze_time(&self) -> Result<(), Error> {
@@ -608,13 +621,6 @@ impl virt::Processor for MshvProcessor<'_> {
     }
 
     fn reset(&mut self) -> Result<(), impl std::error::Error + Send + Sync + 'static> {
-        use virt::vp::AccessVpState;
-
-        let vp_info = self.inner.vp_info;
-        self.access_state(Vtl::Vtl0)
-            .reset_all(&vp_info)
-            .map_err(|e| ErrorInner::ResetState(Box::new(e)))?;
-
         self.reset_synic_state();
 
         Ok::<(), Error>(())
@@ -670,6 +676,8 @@ enum ErrorInner {
     GetPartitionProperty(#[source] KernelError),
     #[error("failed to set partition property")]
     SetPartitionProperty(#[source] KernelError),
+    #[error("failed to scrub partition")]
+    ScrubPartition(#[source] io::Error),
     #[error("register access error")]
     Register(#[source] KernelError),
     #[cfg(guest_arch = "x86_64")]

vmm_core/virt_mshv/src/x86_64/mod.rs

@@ -411,6 +411,8 @@ impl virt::ResetPartition for MshvPartition {
     fn reset(&self) -> Result<(), Error> {
         use virt::x86::vm::AccessVmState;
 
+        self.inner.scrub_partition()?;
+
         for irq in 0..virt::irqcon::IRQ_LINES as u8 {
             self.inner.irq_routes.set_irq_route(irq, None);
         }