diff --git a/src/crimson/os/seastore/object_data_handler.cc b/src/crimson/os/seastore/object_data_handler.cc
index df29ea82366..a4a9ace2ff3 100644
--- a/src/crimson/os/seastore/object_data_handler.cc
+++ b/src/crimson/os/seastore/object_data_handler.cc
@@ -415,6 +415,7 @@ private:
       actual_write_size -= left_ext_size;
       left_ext_size = 0;
       left_operation = overwrite_operation_t::OVERWRITE_ZERO;
+    // FIXME: left_paddr can be absolute and pending
     } else if (left_paddr.is_relative() ||
 	       left_paddr.is_delayed()) {
       aligned_data_size += left_ext_size;
@@ -426,6 +427,7 @@ private:
       actual_write_size -= right_ext_size;
       right_ext_size = 0;
       right_operation = overwrite_operation_t::OVERWRITE_ZERO;
+    // FIXME: right_paddr can be absolute and pending
     } else if (right_paddr.is_relative() ||
 	       right_paddr.is_delayed()) {
       aligned_data_size += right_ext_size;
diff --git a/src/crimson/os/seastore/transaction_manager.h b/src/crimson/os/seastore/transaction_manager.h
index 2514d743011..fddd1e2eece 100644
--- a/src/crimson/os/seastore/transaction_manager.h
+++ b/src/crimson/os/seastore/transaction_manager.h
@@ -355,6 +355,7 @@ public:
     paddr_t existing_paddr,
     extent_len_t length) {
     LOG_PREFIX(TransactionManager::map_existing_extent);
+    // FIXME: existing_paddr can be absolute and pending
     ceph_assert(existing_paddr.is_absolute());
     assert(t.is_retired(existing_paddr, length));