Messages in this thread | | | Subject | Re: [V2][PATCH] cgroup: fix memory leak caused by missing cgroup_bpf_offline | From | Quanyang Wang <> | Date | Wed, 20 Oct 2021 13:22:06 +0800 |
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Hi Ming,
On 10/20/21 10:17 AM, Ming Lei wrote: > On Tue, Oct 19, 2021 at 07:10:26PM +0200, Michal Koutný wrote: >> Hi. >> >> On Tue, Oct 19, 2021 at 06:41:14PM +0800, Quanyang Wang <quanyang.wang@windriver.com> wrote: >>> So I add 2 "Fixes tags" here to indicate that 2 commits introduce two >>> different issues. >> >> AFAIU, both the changes are needed to cause the leak, a single patch >> alone won't cause the issue. Is that correct? (Perhaps not as I realize, >> see below.) >> >> But on second thought, the problem is the missing percpu_ref_exit() in >> the (root) cgroup release path and percpu counter would allocate the >> percpu_count_ptr anyway, so 4bfc0bb2c60e is only making the leak more >> visible. Is this correct? >> >> I agree the commit 2b0d3d3e4fcf ("percpu_ref: reduce memory footprint of >> percpu_ref in fast path") alone did nothing wrong. > > If only precpu_ref data is leaked, it is fine to add "Fixes: 2b0d3d3e4fcf", > I thought cgroup_bpf_release() needs to release more for root cgroup, but > looks not true. For now, I can only observe that precpu_ref data is leaked when running ltp testsuite. Thanks, Quanyang > > > Thanks, > Ming >
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