Port-xen archive

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]

can't attach the amd64-install.img file with read-only access



It looks like the kernel doesn't expect a "dk" block device to be
read-only.

I'm trying to offer an adm64-install.img file to a domU as follows:

disk = [
     'format=raw, vdev=0x6, access=ro, target=/images/NetBSD-9.99.64-amd64-install.img'
]
extra = "root=dk1"

Here's what happens

[   1.0000000] xenbus0 at hypervisor0: Xen Virtual Bus Interface
[   1.0000000] xencons0 at hypervisor0: Xen Virtual Console Driver
[   1.0000000] entropy: WARNING: extracting entropy too early
[   2.0040596] xenbus0: can't get state for device/suspend/event-channel (2)
[   2.0040596] xbd0 at xenbus0 id 6: Xen Virtual Block Device Interface
[   2.0100586] xennet0 at xenbus0 id 0: Xen Virtual Network Interface
[   2.0100586] xennet0: backend features 0x4<RX-COPY>
[   2.0100586] pool redzone disabled for 'xnfrx'
[   2.0100586] xennet0: MAC address 00:16:3e:48:de:51
[   2.0110604] xbd0: 3814 MB, 512 bytes/sect x 7811072 sectors
[   2.0110604] xbd0: backend features 0x1<CACHE-FLUSH>
[   2.0120591] balloon0 at xenbus0 id 0: Xen Balloon driver
[   2.0120591] balloon0: current reservation: 4096000 KiB
[   2.0250884] dk0 at xbd0: "EFI system", 262144 blocks at 2048, type: msdos
[   2.0250884] dk1 at xbd0: "2de8ef15-25bf-444d-a440-1bcfb035c514", 7544832 blocks at 264192, type: ffs
[   2.0260598] swwdog0: software watchdog initialized
[   2.0260598] WARNING: 1 error while detecting hardware; check system log.
[   2.0260598] boot device: dk1
[   2.0260598] opendisk: can't open dev dk1 (30)
[   2.0260598] root on dk1opendisk: can't open dev dk0 (30)
[   2.0260598] opendisk: can't open dev dk1 (30)

[   2.0260598] vfs_mountroot: can't open root device
[   2.0260598] cannot mount root, error = 30
[   2.0260598] root device (default dk1):


If I change the access mode to "rw" it works fine, but then the root
filesystem is mounted "rw" too, even on the install image:

[   2.0300698] dk0 at xbd0: "EFI system", 262144 blocks at 2048, type: msdos
[   2.0300698] dk1 at xbd0: "2de8ef15-25bf-444d-a440-1bcfb035c514", 7544832 blocks at 264192, type: ffs
[   2.0311210] swwdog0: software watchdog initialized
[   2.0311210] WARNING: 1 error while detecting hardware; check system log.
[   2.0311210] boot device: dk1
[   2.0320665] root on dk1
[   2.0430645] xenbus0: can't get state for device/suspend/event-channel (2)

[[ .... ]]

# df
Filesystem   1K-blocks      Used     Avail %Cap MountedOn
/dev/dk1       3648078   2641724    823952  76% /
tmpfs          3907632         8   3907624   0% /tmp
# mount
/dev/dk1 on / type ffs (local)
tmpfs on /tmp type tmpfs (local)


Is this intended?  How might I allow for a read-only xbd0 and thus
read-only root on dk1?

--
					Greg A. Woods <gwoods%acm.org@localhost>

Kelowna, BC     +1 250 762-7675           RoboHack <woods%robohack.ca@localhost>
Planix, Inc. <woods%planix.com@localhost>     Avoncote Farms <woods%avoncote.ca@localhost>

Attachment: pgp2wxHEiSJTM.pgp
Description: OpenPGP Digital Signature



Home | Main Index | Thread Index | Old Index