Xen on FreeBSD 11: Cannot boot from QCOW2 properly (waiting for XENBUS, xenbusb_nop_confighook_cb)

[Alexander Nusov]

Cool, many thanks!



--

Alex


---- On Wed, 25 Jan 2017 14:50:51 +0300 Roger Pau Monné <roger.pau at citrix.com> wrote ----




On Wed, Jan 25, 2017 at 02:20:55PM +0300, Alexander Nusov wrote: 

> Got it, thanks. 

> 

> 

> 

> I found a workaround to avoid XENBUS delay in Linux DomUs by adding xen_platform_pci = 0 to the configuration file. 

> 

> So FreeBSD 11.0 Dom0 can boot Linux guests and Windows Server (FreeBSD DomU still stuck on xenbusb_nop_confighook_cb) from QCOW2 images (also works with QCOW2 overlay images) 

> 

 

On FreeBSD you can boot with QCOW2 by not setting "xen_platform_pci = 0" on the 

guest config file and adding "hw.xen.disable_pv_disks=1" to the 

/boot/loader.conf file of the guest. This will prevent FreeBSD from using the 

PV disk, but you will still get the PV network interfaces. 

 

> 

> Can you tell me please what is the disadvantage of not using /dev/xen/vbd devices and drivers in guests? like slow I/O? 

 

Slow IO only. 

 

> May it lead to data corruption? 

 

No.