Re: [PATCH v2 4/4] mm/slub: Fix sysfs shrink circular locking dependency

[Qian Cai]

> On Apr 27, 2020, at 9:39 PM, Waiman Long <longman@xxxxxxxxxx> wrote:
> 
> The sequence that was prevented by this patch is "kn->count --> mem_hotplug_lock.rwsem". This sequence isn't directly in the splat. Once this link is broken, the 3-lock circular loop cannot be formed. Maybe I should modify the commit log to make this point more clear.

I donât know what you are talking about. Once trylock succeed once, you will have kn->count â> cpu/memory_hotplug_lock.