slightly cleaner timeout solution

.bazelrc

diff --git a/.bazelrc b/.bazelrc
index ab8b222..669c58a 100644
--- a/.bazelrc
+++ b/.bazelrc
@@ -85,15 +85,15 @@
 # that fires when --test_tag_filters is set by both k_common and this config.
 test:virt_ast10x0 --test_tag_filters=-integration,-do_not_build,-do_not_run_test,-kernel_doc_test,-hardware
 
-# Stress test configs — identical to the base configs but with --no-timeout in
-# --run_under and +stress in test_tag_filters so only stress targets are run.
+# Stress test configs — same platform/build flags as the base configs but with
+# --timeout 0 in --run_under so the runner blocks indefinitely until FAIL.
 common:stress_virt_ast10x0 --platforms=//target/ast10x0
 common:stress_virt_ast10x0 --//target/ast10x0:qemu=true
 build:stress_virt_ast10x0  --build_tag_filters=-do_not_build,-kernel_doc_test
 run:stress_virt_ast10x0    --run_under="//target/ast10x0/harness:qemu_runner \
-  --no-timeout --cpu cortex-m4 --machine ast1030-evb --image "
+  --timeout 0 --cpu cortex-m4 --machine ast1030-evb --image "
 test:stress_virt_ast10x0   --run_under="//target/ast10x0/harness:qemu_runner \
-  --no-timeout --cpu cortex-m4 --machine ast1030-evb --image "
+  --timeout 0 --cpu cortex-m4 --machine ast1030-evb --image "
 common:stress_k_ast1060_evb --platforms=//target/ast10x0
 build:stress_k_ast1060_evb  --build_tag_filters=-do_not_build,-kernel_doc_test
 test:stress_k_ast1060_evb   --local_test_jobs=1

target/ast10x0/harness/qemu_runner.py

diff --git a/target/ast10x0/harness/qemu_runner.py b/target/ast10x0/harness/qemu_runner.py
index 0ea4e46..e2a53ed 100644
--- a/target/ast10x0/harness/qemu_runner.py
+++ b/target/ast10x0/harness/qemu_runner.py
@@ -41,7 +41,6 @@
 
 PASS_SENTINEL = b"TEST_RESULT:PASS"
 FAIL_SENTINEL = b"TEST_RESULT:FAIL"
-TIMEOUT_SECONDS = 30
 
 
 def _parse_args():
@@ -56,9 +55,10 @@
         "--qemu-args", nargs="*", help="Extra arguments to pass to qemu"
     )
     parser.add_argument(
-        "--no-timeout",
-        action="store_true",
-        help="Run indefinitely; for stress tests that never emit PASS",
+        "--timeout",
+        type=int,
+        default=30,
+        help="Seconds to wait for a test result sentinel (0 = no timeout, default: 30)",
     )
     return parser.parse_args()
 
@@ -159,17 +159,14 @@
             stdout_thread.start()
 
             try:
-                if args.no_timeout:
-                    proc.wait()
-                else:
-                    proc.wait(timeout=TIMEOUT_SECONDS)
+                proc.wait(timeout=args.timeout if args.timeout > 0 else None)
             except KeyboardInterrupt:
                 proc.kill()
                 proc.wait()
             except subprocess.TimeoutExpired:
                 _LOG.error(
                     "Test timed out after %ds — no sentinel detected",
-                    TIMEOUT_SECONDS,
+                    args.timeout,
                 )
                 proc.kill()
                 proc.wait()