The interaction between ptrace and freezer is complicated (as ptrace in general),so there are known cases when spurious cgroup transitions (frozen <-> non frozen <-> frozen ) can happen.
When test ran for 8 times it got failed 5 times. I have noticed intermittent failure on x86_64, arm64 hikey device and qemu_arm64.
Does it create any difficulties? If so, I'll send a diff to ignore the result of this test for now.
No difficulties. I will mark this test case as known failure.
This patch implements 9 tests for the freezer controller for cgroup v2:
- ptrace test: the test checks that it's possible to attach to
a process in a frozen cgroup, get some information and detach, and the cgroup will remain frozen.
selftests cgroup test_freezer failed because of the sys entry path not found.
Can you, please, elaborate on this?
I see this failure output on screen and sharing log here.
Please find full test log here, https://lkft.validation.linaro.org/scheduler/job/825346#L673