On Tue, Jun 20, 2017 at 02:58:14PM -0700, Andrew Morton wrote: > On Tue, 20 Jun 2017 16:45:12 -0400 Tejun Heo <[email protected]> wrote: > > > bf5eb3de3847 ("slub: separate out sysfs_slab_release() from > > sysfs_slab_remove()") made slub sysfs file removals synchronous to > > kmem_cache shutdown. Unfortunately, this created a possible ABBA > > deadlock between slab_mutex and sysfs draining mechanism triggering > > the following lockdep warning. > > > > ... > > > > Signed-off-by: Tejun Heo <[email protected]> > > Reported-by: Steven Rostedt (VMware) <[email protected]> > > Tested-by: Steven Rostedt (VMware) <[email protected]> > > Fixes: bf5eb3de3847 ("slub: separate out sysfs_slab_release() from > > sysfs_slab_remove()") > > Do you think we should add cc:stable [4.11+]?
I think we'd risk more by backporting it through -stable than keeping the bug there. The bug is very difficult to hit. Writing to a slub sysfs file has to race against kmem_cache destruction and AFAICS all slub sysfs files are for debugging. Thanks. -- tejun
