fix: Fix rare failure in pause resume test

Test with 1 vCPU when running the KVMCLOCK_CTRL tests so we don't error on intermittent issue with the soft lockup watchdog. Signed-off-by: Jack Thomson <[email protected]>
firecracker-microvm · Feb 6, 2025 · 89f2cb2 · 89f2cb2
1 parent 567b1ea
commit 89f2cb2
Showing 1 changed file with 6 additions and 1 deletion.
diff --git a/tests/integration_tests/functional/test_pause_resume.py b/tests/integration_tests/functional/test_pause_resume.py
@@ -141,7 +141,12 @@ def test_kvmclock_ctrl(uvm_plain_any):
     microvm = uvm_plain_any
     microvm.help.enable_console()
     microvm.spawn()
-    microvm.basic_config()
+
+    # With 2 vCPUs under certain conditions soft lockup warnings can rarely be in dmesg causing this test to fail.
+    # Example of the warning: `watchdog: BUG: soft lockup - CPU#0 stuck for (x)s! [(udev-worker):758]`
+    # With 1 vCPU this intermittent issue doesn't occur. If the KVM_CLOCK_CTRL IOCTL is not made
+    # the test will fail with 1 vCPU, so we can assert the call to the IOCTL is made.
+    microvm.basic_config(vcpu_count=1)
     microvm.add_net_iface()
     microvm.start()