Re: New syscons bugs: shutdown -r doesn't execute rc.d sequence and others

On 30.03.2017 14:23, Andriy Gapon wrote:
> On 30/03/2017 12:34, Andrey Chernov wrote:
>> On 30.03.2017 12:23, Andrey Chernov wrote:
>>> Yes, only for reboot/shutdown. The system does not do anythings wrong
>>> even under high load. On reboot or hang those lines are never printed:
>>>
>>> kernel: Waiting (max 60 seconds) for system process `vnlru' to stop...done
>>> kernel: Waiting (max 60 seconds) for system process `bufdaemon' to
>>> stop...done
>>> kernel: Waiting (max 60 seconds) for system process `syncer' to stop...
>>> kernel: Syncing disks, vnodes remaining...5 3 0 1 0 0 done
>>> kernel: All buffers synced.
>>> (it is from 10-stable sample, old -current samples are lost)
>>>
>>> Moreover, GELI swap deactivation lines are never printed too (I already
>>> mention that I change swap to normal, but nothing is changed).
>>
>> I start to have raw guess that _any_ kernel printf in shutdown mode
>> cause not printf but premature reboot.
> 
> This sounds somewhat familiar...
> I vaguely recall an opposite issue that happened in the past.  After one of my
> changes the reboot started hanging for one user.  Turned out that the actual bug
> was always there, but previously the system rebooted because of a printf that
> caused a LOR (between spinlocks, AFAIR), witness tried to report it... using
> printf, and that recursed and there was a triple fault in the end.
> 
> Let me try to dig some details, maybe the current issue is related in some ways.
> 
> By chance, do you have WITNESS but not WITNESS_SKIPSPIN in your kernel config?

No, I don't have WITNESS*
I think removing all vt* lines from the kernel confing (and leaving sc)
will be enough to reproduce it, but I am not sure.