[dm-devel] linux-next: Boot hangs 3 minutes with device mapper on s390

[Mikulas Patocka]

On Mon, 4 Mar 2019, Mike Snitzer wrote:

> Hi,
> 
> Alexander reported this same boot hang in another thread.  I was able to
> reproduce using an x86_64 .config that Alexander provided.
> 
> I've pushed this fix out to linux-next:
> https://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm.git/commit/?h=dm-5.1&id=be2c5301817833f692aadb2e5fa209582db01d3b
> 
> If you could verify this fix works for you I'd appreciate it.
> 
> Thanks,
> Mike

So, remove this no-clone optimization and stage it for the next merge 
window. There's something we don't understand, so don't merge it. This 
patch is just papering over the problem.

"Stacking noclone targets creates more complexity than is tolerable" just 
means that no one knows what is hapenning there.

Meanwile, we could get access to the system that reports hangs and test it 
there.

Mikulas