Re: [PATCH v2 bpf-next] bpf: fix cgroup bpf release synchronization

2019-06-26 Thread Song Liu
> On Jun 25, 2019, at 2:38 PM, Roman Gushchin wrote: > > Since commit 4bfc0bb2c60e ("bpf: decouple the lifetime of cgroup_bpf > from cgroup itself"), cgroup_bpf release occurs asynchronously > (from a worker context), and before the release of the cgroup itself. > > This introduced a previous

Re: [PATCH v2 bpf-next] bpf: fix cgroup bpf release synchronization

2019-06-26 Thread Alexei Starovoitov
On Tue, Jun 25, 2019 at 2:39 PM Roman Gushchin wrote: > > Since commit 4bfc0bb2c60e ("bpf: decouple the lifetime of cgroup_bpf > from cgroup itself"), cgroup_bpf release occurs asynchronously > (from a worker context), and before the release of the cgroup itself. > > This introduced a previously n

[PATCH v2 bpf-next] bpf: fix cgroup bpf release synchronization

2019-06-25 Thread Roman Gushchin
Since commit 4bfc0bb2c60e ("bpf: decouple the lifetime of cgroup_bpf from cgroup itself"), cgroup_bpf release occurs asynchronously (from a worker context), and before the release of the cgroup itself. This introduced a previously non-existing race between the release and update paths. E.g. if a l