[pvmfw] Ensure the /memory node in DT contains only one range
As specified in crosvm. Print a warning if more than one memory
ranges are detected in the DT passed to pvmfw.
Bug: 284462758
Test: atest MicrodroidHostTests
Change-Id: I909ccfcbc304bbf0d6ea38bf88927976b8aab022
diff --git a/pvmfw/src/fdt.rs b/pvmfw/src/fdt.rs
index efb354c..319100f 100644
--- a/pvmfw/src/fdt.rs
+++ b/pvmfw/src/fdt.rs
@@ -124,8 +124,24 @@
node.setprop(cstr!("bootargs"), bootargs.to_bytes_with_nul())
}
-/// Check if memory range is ok
-fn validate_memory_range(range: &Range<usize>) -> Result<(), RebootReason> {
+/// Reads and validates the memory range in the DT.
+///
+/// Only one memory range is expected with the crosvm setup for now.
+fn read_and_validate_memory_range(fdt: &Fdt) -> Result<Range<usize>, RebootReason> {
+ let mut memory = fdt.memory().map_err(|e| {
+ error!("Failed to read memory range from DT: {e}");
+ RebootReason::InvalidFdt
+ })?;
+ let range = memory.next().ok_or_else(|| {
+ error!("The /memory node in the DT contains no range.");
+ RebootReason::InvalidFdt
+ })?;
+ if memory.next().is_some() {
+ warn!(
+ "The /memory node in the DT contains more than one memory range, \
+ while only one is expected."
+ );
+ }
let base = range.start;
if base != MEM_START {
error!("Memory base address {:#x} is not {:#x}", base, MEM_START);
@@ -142,7 +158,7 @@
error!("Memory size is 0");
return Err(RebootReason::InvalidFdt);
}
- Ok(())
+ Ok(range)
}
fn patch_memory_range(fdt: &mut Fdt, memory_range: &Range<usize>) -> libfdt::Result<()> {
@@ -600,11 +616,7 @@
RebootReason::InvalidFdt
})?;
- let memory_range = fdt.first_memory_range().map_err(|e| {
- error!("Failed to read memory range from DT: {e}");
- RebootReason::InvalidFdt
- })?;
- validate_memory_range(&memory_range)?;
+ let memory_range = read_and_validate_memory_range(fdt)?;
let bootargs = read_bootargs_from(fdt).map_err(|e| {
error!("Failed to read bootargs from DT: {e}");