On Sat, Jan 02, 2016 at 06:59:16PM -0600, Serge E. Hallyn wrote: > On Sat, Jan 02, 2016 at 01:50:49PM -0800, Jeremiah Mahler wrote: > > Serge, > > > > On Sat, Jan 02, 2016 at 12:24:16PM -0600, Serge E. Hallyn wrote: > > [...] > > > > > > Tried to reproduce with setting CONFIG_CFQ_GROUP_IOSCHED=y, but did not > > > succeed. Could you send me the .config? Also, if someone could send > > > the objdump -d output that might help. Though really, it seems clear > > > that current->nsproxy must be NULL. Hm, that's right - we used to have > > > that issue in pidns (or was it netns) during process exit. I don't know > > > that I'll get time this afternoon, but I'll look into it asap. > > > > > > thanks. > > > > Attached is the .config I used. I can send an objdump, but do you want > > a dump of the kernel, where the cgroup code is? > > > > -- > > - Jeremiah Mahler > > Thanks - Shoulda looked at the exit path before - exit_io_context is called > after exit_task_namespaces(). > > I'll have to figure out the best way to handle this. In the past we've > restructured exit code to ensure that anything wanting to dereference > nsproxy happened before exit_task_namespaces(). However, this is only > happening in a debug stmt at blkg_path() in > http://lxr.free-electrons.com/source/include/linux/blk-cgroup.h#L344 > so simply returning the init_cgroup_namespace is actually the right thing > to do. I'm tempted to add a init_cgroup_path() which ignores namespaces, > for use in debugging statements.
Or really I think it makes more sense to make cgroup_path_ns() take the namespace into account, switch over cgroup_path() users who want _ns(), and leave cgroup_path() using the initial cgroup namespace. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
