panic: pmap_demote_section: No l2_bucket for wired mapping

[Michael Tuexen]

> On 22 Mar 2015, at 13:15, Olivier Houchard <mlfbsd at ci0.org> wrote:
> 
> On Sun, Mar 22, 2015 at 01:05:43PM -0500, Michael Tuexen wrote:
>>> On 22 Mar 2015, at 10:19, Olivier Houchard <mlfbsd at ci0.org> wrote:
>>> 
>>> On Sun, Mar 22, 2015 at 06:54:06AM -0500, Michael Tuexen wrote:
>>>> Dear all,
>>>> 
>>> 
>>> Hi Michael, 
>>> 
>>>> running head on a Raspberry Pi became unstable. When running
>>>> r280329 for a while (the machine is exposed to the Internet, so
>>>> ssh logins are continuously tried), the machine panics:
>>>> 
>>>> panic: pmap_demote_section: No l2_bucket for wired mapping
>>>> 
>>>> It might be related to
>>>> https://svnweb.freebsd.org/changeset/base/280324
>>>> 
>>>> Any idea what is going on?
>>>> 
>>> 
>>> Doest backing rev 280324 out fixes it ? I'm at a loss as to why my commit 
>> OK, testing done. Backing out 280324 does NOT help. So the issue is not related
>> to this patch.
>> Disabling superpages helps to work around the issue.
>> 
> 
> Is there any specific workload on your RPi, beside getting ssh-scanned ?
No. I saw the problem by just letting it sitting around. Sometime it
panics pretty fast (order of a minute after reboot). I can force it
by doing a git pull on a large project (like wireshark).
> Who has PID 15, and suffer such an unfortunate doom while trying to demote
> pages ?
I think it is the pagedaemon.

Best regards
Michael
> 
> Regards,
> 
> Olivier
>