Re: [PATCH] cgroup: fail if monitored file and event_control are in different cgroup

2013-02-18 Thread Tejun Heo
On Mon, Feb 18, 2013 at 02:13:35PM +0800, Li Zefan wrote: > If we pass fd of memory.usage_in_bytes of cgroup A to cgroup.event_control > of cgroup B, then we won't get memory usage notification from A but B! > > What's worse, if A and B are in different mount hierarchy, we'll end up > accessing NU

Re: [PATCH] cgroup: fail if monitored file and event_control are in different cgroup

2013-02-18 Thread Kirill A. Shutemov
On Mon, Feb 18, 2013 at 02:13:35PM +0800, Li Zefan wrote: > If we pass fd of memory.usage_in_bytes of cgroup A to cgroup.event_control > of cgroup B, then we won't get memory usage notification from A but B! > > What's worse, if A and B are in different mount hierarchy, we'll end up > accessing NU

[PATCH] cgroup: fail if monitored file and event_control are in different cgroup

2013-02-17 Thread Li Zefan
If we pass fd of memory.usage_in_bytes of cgroup A to cgroup.event_control of cgroup B, then we won't get memory usage notification from A but B! What's worse, if A and B are in different mount hierarchy, we'll end up accessing NULL pointer! Disallow this kind of invalid usage. Signed-off-by: Li