Re: Deadlock due to "cpuset: Make cpuset hotplug synchronous"

From: Qian Cai
Date: Wed Apr 01 2020 - 22:00:37 EST




> On Mar 25, 2020, at 3:19 PM, Tejun Heo <tj@xxxxxxxxxx> wrote:
>
> On Wed, Mar 25, 2020 at 03:16:56PM -0400, Qian Cai wrote:
>> The linux-next commit a49e4629b5ed (âcpuset: Make cpuset hotplug synchronousâ)
>> introduced real deadlocks with CPU hotplug as showed in the lockdep splat, since it is
>> now making a relation from cpu_hotplug_lock â> cgroup_mutex.
>
> Prateek, can you please take a look? Given that the merge window is just around
> the corner, we might have to revert and retry later if it can't be resolved
> quickly.

Tejun, can you back off this commit now given it seems nobody is trying to rescue it?