Re: [RFC PATCH] mm: memcg: fix css double put in mem_cgroup_iter

2017-07-27 Thread Michal Hocko
On Thu 27-07-17 11:30:50, Wenwei Tao wrote: > 2017-07-26 21:44 GMT+08:00 Michal Hocko : > > On Wed 26-07-17 21:07:42, Wenwei Tao wrote: [...] > >> I think there is a css double put in mem_cgroup_iter. Under reclaim, > >> we call mem_cgroup_iter the first time with prev == NULL,

Re: [RFC PATCH] mm: memcg: fix css double put in mem_cgroup_iter

2017-07-27 Thread Michal Hocko
On Thu 27-07-17 11:30:50, Wenwei Tao wrote: > 2017-07-26 21:44 GMT+08:00 Michal Hocko : > > On Wed 26-07-17 21:07:42, Wenwei Tao wrote: [...] > >> I think there is a css double put in mem_cgroup_iter. Under reclaim, > >> we call mem_cgroup_iter the first time with prev == NULL, and we get > >>

Re: [RFC PATCH] mm: memcg: fix css double put in mem_cgroup_iter

2017-07-26 Thread Wenwei Tao
2017-07-26 21:44 GMT+08:00 Michal Hocko : > On Wed 26-07-17 21:07:42, Wenwei Tao wrote: >> From: Wenwei Tao >> >> By removing the child cgroup while the parent cgroup is >> under reclaim, we could trigger the following kernel panic >> on kernel 3.10:

Re: [RFC PATCH] mm: memcg: fix css double put in mem_cgroup_iter

2017-07-26 Thread Wenwei Tao
2017-07-26 21:44 GMT+08:00 Michal Hocko : > On Wed 26-07-17 21:07:42, Wenwei Tao wrote: >> From: Wenwei Tao >> >> By removing the child cgroup while the parent cgroup is >> under reclaim, we could trigger the following kernel panic >> on kernel 3.10: >>

Re: [RFC PATCH] mm: memcg: fix css double put in mem_cgroup_iter

2017-07-26 Thread Michal Hocko
On Wed 26-07-17 21:07:42, Wenwei Tao wrote: > From: Wenwei Tao > > By removing the child cgroup while the parent cgroup is > under reclaim, we could trigger the following kernel panic > on kernel 3.10: >

Re: [RFC PATCH] mm: memcg: fix css double put in mem_cgroup_iter

2017-07-26 Thread Michal Hocko
On Wed 26-07-17 21:07:42, Wenwei Tao wrote: > From: Wenwei Tao > > By removing the child cgroup while the parent cgroup is > under reclaim, we could trigger the following kernel panic > on kernel 3.10: > > kernel BUG at

[RFC PATCH] mm: memcg: fix css double put in mem_cgroup_iter

2017-07-26 Thread Wenwei Tao
From: Wenwei Tao By removing the child cgroup while the parent cgroup is under reclaim, we could trigger the following kernel panic on kernel 3.10: kernel BUG at kernel/cgroup.c:893! invalid

[RFC PATCH] mm: memcg: fix css double put in mem_cgroup_iter

2017-07-26 Thread Wenwei Tao
From: Wenwei Tao By removing the child cgroup while the parent cgroup is under reclaim, we could trigger the following kernel panic on kernel 3.10: kernel BUG at kernel/cgroup.c:893! invalid opcode: [#1] SMP CPU: 1