diff --git a/sky/skylet/log_lib.py b/sky/skylet/log_lib.py
index deeed4429e9..ba04fea5d49 100644
--- a/sky/skylet/log_lib.py
+++ b/sky/skylet/log_lib.py
@@ -259,6 +259,9 @@ def run_with_log(
                 return proc.returncode, stdout, stderr
             return proc.returncode
         except KeyboardInterrupt:
+            # Send SIGINT to the process directly, otherwise, the underlying process
+            # will only killed after the python program exits, causing the stream
+            # handling stuck at `readline`.
             os.killpg(proc.pid, signal.SIGINT)
             raise