Hello, Djalal. On Wed, Mar 27, 2024 at 11:53:22PM +0100, Djalal Harouni wrote: > This patch series adds support to freeze the task cgroup hierarchy > that is on a default cgroup v2 without going through kernfs interface. > > For some cases we want to freeze the cgroup of a task based on some > signals, doing so from bpf is better than user space which could be > too late. > > Planned users of this feature are: tetragon and systemd when freezing > a cgroup hierarchy that could be a K8s pod, container, system service > or a user session. > > Patch 1: cgroup: add cgroup_freeze_no_kn() to freeze a cgroup from bpf > Patch 2: bpf: add bpf_task_freeze_cgroup() to freeze the cgroup of a task > Patch 3: selftests/bpf: add selftest for bpf_task_freeze_cgroup It bothers me a bit that it's adding a dedicated interface for something which already has a defined userspace interface. Would it be better to have kfunc wrappers for kernel_read() and kernel_write()? Thanks. -- tejun