On Jan 16, 7:21pm, Manuel Bouyer wrote:
}
} what problem are you trying to solve with this commit to sys/dev/vnd.c ?
} revision 1.251
} date: 2015/11/09 17:41:24; author: christos; state: Exp; lines: +3 -5
} Return ENXIO if the get ioctl exceeds the number of configured devices.
} XXX: pullup-7
The issue was that under some conditions, vnconfig -l would
loop forever, displaying:
vnd<i>: not in use
vnd<j>: not in use
vnd<k>: not in use
...
I don't recall the exact trigger condition, but I have seen it happen.
} This broke vnconfig -l (and so Xen block-device scripts):
} xen1:/tmp#vnconfig -l
} vnd0: /domains (/dev/wd0f) inode 3
} vnconfig: VNDIOCGET: Device not configured
It stops an older vnconfig with a newer kernel from looping
forever. Exactly how old vnconfig has to be and how new the kernel
has to be is left as an exercise for the reader. :->
} There are 7 more vnd devices in /dev/ waiting to be configured on this system.
}
} This has been pulled up to netbsd-7 and netbsd-7-0 as part of
} ticket 1038, so vnconfig (and Xen dom0) is broken here too,
} as reported in PR 50659
When trying to locate a free vnd(4), xl (technically, it calls
out to a script that) does this:
-----
# Store the list of available vnd(4) devices in
#``available_disks'', and mark them as ``free''.
list=`ls -1 /dev/vnd[0-9]*d | sed "s,/dev/vnd,,;s,d,," | sort -n
`
for i in $list; do
disk="vnd$i"
available_disks="$available_disks $disk"
eval $disk=free
done
# Mark the used vnd(4) devices as ``used''.
for disk in `sysctl hw.disknames`; do
case $disk in
vnd[0-9]*) eval $disk=used ;;
esac
done
# Configure the first free vnd(4) device.
for disk in $available_disks; do
eval status=\$$disk
if [ "$status" = "free" ] && \
vnconfig /dev/${disk}d $xparams >/dev/null; then
device=/dev/${disk}d
break
fi
done
if [ x$device = x ] ; then
error "no available vnd device"
fi
-----
It would appear that the call to vnconfig is failing. The question
is, why? What happens if you have 9 or fewer /dev/vnds? My thought
here is about sort order where vnd10 would come before vnd2 and
what happens if you try to configure them out of order.
}-- End of excerpt from Manuel Bouyer
