fixup! Move calling 'dump_on_crash' from each driver, to common VCpu, and move logic to its own module

Signed-off-by: Ludvig Liljenberg <[email protected]>

Author: ludfjig

src/hyperlight_host/src/hypervisor/crashdump.rs

@@ -6,35 +6,31 @@ use super::Hypervisor;
 use crate::{new_error, Result};
 
 /// Dump registers + memory regions + raw memory to a tempfile
-#[cfg(crashdump)]
 pub(crate) fn crashdump_to_tempfile(hv: &dyn Hypervisor) -> Result<()> {
-    let mem_regions = hv.get_memory_regions();
-    let mem_size = mem_regions
-        .iter()
-        .map(|region| region.host_region.len())
-        .sum();
-    let mem_start_addr = mem_regions[0].host_region.start as *const u8;
-
-    if mem_start_addr.is_null() || mem_size == 0 {
-        return Err(new_error!(
-            "Invalid address or size while creating crashdump"
-        ));
-    }
-
     let mut temp_file = NamedTempFile::with_prefix("mem")?;
-
     let hv_details = format!("{:#x?}", hv);
 
-    // write hypervisor details such as registers, memory regions, etc.
+    // write hypervisor details such as registers, info about mapped memory regions, etc.
     temp_file.write_all(hv_details.as_bytes())?;
-    // write memory dump
     temp_file.write_all(b"================ MEMORY DUMP =================\n")?;
-    // SAFETY: Address and size non-null and non-zero
-    unsafe {
-        let slice = std::slice::from_raw_parts(mem_start_addr, mem_size);
-        temp_file.write_all(slice)?;
-        temp_file.flush()?;
+
+    // write the raw memory dump for each memory region
+    for region in hv.get_memory_regions() {
+        if region.host_region.start == 0 || region.host_region.is_empty() {
+            continue;
+        }
+        // SAFETY: we got this memory region from the hypervisor so should never be invalid
+        let region_slice = unsafe {
+            std::slice::from_raw_parts(
+                region.host_region.start as *const u8,
+                region.host_region.len(),
+            )
+        };
+        temp_file.write_all(region_slice)?;
     }
+    temp_file.flush()?;
+
+    // persist the tempfile to disk
     let persist_path = temp_file.path().with_extension("dmp");
     temp_file
         .persist(&persist_path)