Re: port-xen/50659: Xen4.5 crash with vnds

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Thu, Mar 24, 2016 at 06:53:20PM +0100, Christoph Badura wrote:
> On Wed, Mar 23, 2016 at 09:23:22AM +0100, Manuel Bouyer wrote:
> > I think it is Xen's problem.
> > I noticed that xen 4.5 starts domUs concurently (/etc/rc.d/xendomains start)
> > which prevented be from upgrading to 4.5 because of concurency problems
> > in my network scripts (local change).
> > 
> > Now if it runs scripts for each block device (or, I guess, each
> > network device) in parallel, then we have a problem.
> 
> xl does indeed run the device hotplug scripts in parallel.  c.f.
> libxl/libxl_device.c:device_hotplug().
> 
> If you looks at the linux hotplug scripts, they do their own serialization
> as appropriate.  "grep -r _lock hotplug/Linux".

I tried to do something with shlock(1) but it doens't work, it's too
slow and xl times out. 
Maybe flock would work but older NetBSD don't have it ...

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
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