Re: port-xen/47899: xen block script does not create vnd devices when needed.

[christos%zoulas.com@localhost (Christos Zoulas)]

On Jun 6,  1:30pm, bouyer%antioche.eu.org@localhost (Manuel Bouyer) wrote:
-- Subject: Re: port-xen/47899: xen block script does not create vnd devices 

| The following reply was made to PR port-xen/47899; it has been noted by GNATS.
| 
| From: Manuel Bouyer <bouyer%antioche.eu.org@localhost>
| To: gnats-bugs%NetBSD.org@localhost
| Cc: port-xen-maintainer%NetBSD.org@localhost, 
gnats-admin%NetBSD.org@localhost,
|         netbsd-bugs%NetBSD.org@localhost, 7heo%7heo.tk@localhost
| Subject: Re: port-xen/47899: xen block script does not create vnd devices
|  when needed.
| Date: Thu, 6 Jun 2013 15:26:16 +0200
| 
|  On Thu, Jun 06, 2013 at 12:05:01PM +0000, Michael van Elst wrote:
|  >  >vnconfig -l works fine for me:
|  >  >ragga:/domains#vnconfig -l
|  >  >vnd0: not in use
|  >  >vnd1: /domains (/dev/raid1f) inode 4
|  >  >vnd2: /domains (/dev/raid1f) inode 11
|  >  >vnd3: /domains (/dev/raid1f) inode 12
|  >  >vnd4: not in use
|  >  >vnd5: not in use
|  >  >vnd6: not in use
|  >  >[...]
|  >  >vnd29: not in use
|  >  >vnd30: not in use
|  >  >vnd31: not in use
|  >  
|  >  vnconfig will clone the driver instance when necessary, but
|  >  never remove it. The first 4 instances are precreated by
|  >  the driver to be compatible with earlier kernels where
|  >  the driver wasn't cloning.
|  
|  but AFAIK vnconfig doesn't know how much instances are available in
|  the kernel. It only checks if existing /dev/vnd* nodes are busy or
|  not: it does a VNDIOCGET for each vnu_unit against /dev/vnd0d
|  (up do cd_ndevs if I read the code properly).
|  I guess cd_ndevs is increased dynamically when devices are used ...

No, this is a bug. Let me fix it. It should not be using cd_ndevs.

christos