Re: 2.6.31.6 pv_ops from xen-4.0.0-rc1 hangs by DomU initrd

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

> >> Without initrd the kernel can't mount / (root).

It looks as the initrd is executing fine. Not sure if the initrd
has switched root, thought it looks as it has.

> >>

.. snip ..
> [    0.118350] IP route cache hash table entries: 1024 (order: 0, 4096
> bytes)
> [    0.119067] TCP established hash table entries: 2048 (order: 2, 16384
> bytes)
> [    0.119120] TCP bind hash table entries: 2048 (order: 2, 16384 bytes)
> [    0.119163] TCP: Hash tables configured (established 2048 bind 2048)
> [    0.119191] TCP reno registered
> [    0.119426] NET: Registered protocol family 1
> [    0.119648] Trying to unpack rootfs image as initramfs...
> [    0.148573] Freeing initrd memory: 5740k freed

This is where the initrd starts.

> [    0.156599] platform rtc_cmos: registered platform RTC device (no PNP
> device found)
> [    0.159750] microcode: no support for this CPU vendor
> [    0.159781] Scanning for low memory corruption every 60 seconds
> [    0.160248] cryptomgr_test used greatest stack depth: 6936 bytes left
> [    0.161942] audit: initializing netlink socket (disabled)
> [    0.162172] type=2000 audit(1264522680.971:1): initialized
> [    0.184661] HugeTLB registered 2 MB page size, pre-allocated 0 pages
> [    0.203417] VFS: Disk quotas dquot_6.5.2
> [    0.203865] Dquot-cache hash table entries: 1024 (order 0, 4096 bytes)
> [    0.207329] msgmni has been set to 111
> [    0.210387] alg: No test for stdrng (krng)
> [    0.211187] Block layer SCSI generic (bsg) driver version 0.4 loaded
> (major 252)
> [    0.211225] io scheduler noop registered
> [    0.211249] io scheduler anticipatory registered
> [    0.211274] io scheduler deadline registered
> [    0.211660] io scheduler cfq registered (default)
> [    0.212643] pci_hotplug: PCI Hot Plug PCI Core version: 0.5
> [    0.214541] Event-channel device installed.
> [    0.232426] blktap_device_init: blktap device major 254
> [    0.233025] blktap_ring_init: blktap ring major: 251
> [    0.243442] registering netback
> [    0.271990] Non-volatile memory driver v1.3
> [    0.272019] Linux agpgart interface v0.103
> [    0.273222] [drm] Initialized drm 1.1.0 20060810
> [    0.273266] Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
> [    0.288968] brd: module loaded
> [    0.295595] loop: module loaded
> [    0.351552] input: Macintosh mouse button emulation as
> /class/input/input0
> [    0.353727] Initialising Xen virtual ethernet driver.
> [    0.354211] console [netcon0] enabled
> [    0.354241] netconsole: network logging started
> [    0.355353] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
> [    0.355700] ohci_hcd: USB 1.1 'Open' Host Controller (OHCI) Driver
> [    0.356190] uhci_hcd: USB Universal Host Controller Interface driver
> [    0.356924] usbcore: registered new interface driver usblp
> [    0.356960] Initializing USB Mass Storage driver...
> [    0.357436] usbcore: registered new interface driver usb-storage
> [    0.357472] USB Mass Storage support registered.
> [    0.357771] usbcore: registered new interface driver libusual
> [    0.358960] PNP: No PS/2 controller found. Probing ports directly.
> [    0.359019] i8042.c: No controller found.
> [    0.360669] mice: PS/2 mouse device common for all mice
> [    0.363284] rtc_cmos rtc_cmos: rtc core: registered rtc_cmos as rtc0
> [    0.364967] cpuidle: using governor ladder
> [    0.364995] cpuidle: using governor menu
> [    0.373218] blkfront: xvda1: barriers enabled
> [    0.375595] usbcore: registered new interface driver hiddev
> [    0.376409] usbcore: registered new interface driver usbhid
> [    0.376442] usbhid: v2.6:USB HID core driver
> [    0.377325] Advanced Linux Sound Architecture Driver Version 1.0.20.
> [    0.380915] blkfront: xvda2: barriers enabled
> [    0.387294] modprobe used greatest stack depth: 6504 bytes left
> [    0.388517] ALSA device list:
> [    0.388542]   No soundcards found.
> [    0.388606] Netfilter messages via NETLINK v0.30.
> [    0.388681] nf_conntrack version 0.5.0 (1024 buckets, 4096 max)
> [    0.390433] ctnetlink v0.93: registering with nfnetlink.
> [    0.392128] ip_tables: (C) 2000-2006 Netfilter Core Team
> [    0.392216] TCP cubic registered
> [    0.392239] Initializing XFRM netlink socket
> [    0.394242] NET: Registered protocol family 10
> [    0.396408] ip6_tables: (C) 2000-2006 Netfilter Core Team
> [    0.396576] IPv6 over IPv4 tunneling driver
> [    0.398545] NET: Registered protocol family 17
> [    0.399342] RPC: Registered udp transport module.
> [    0.399372] RPC: Registered tcp transport module.
> [    0.399484] Using IPI No-Shortcut mode
> [    0.400577] registered taskstats version 1
> [    0.400635] XENBUS: Device with no driver: device/console/0
> [    0.400706]   Magic number: 1:252:3141
> [    0.400934] Freeing unused kernel memory: 388k freed
> [    0.405803] Write protecting the kernel text: 3816k
> [    0.407898] Write protecting the kernel read-only data: 1768k
> 

I think the problem is you have made the console not be hvc0. Or in other
words, the rest of the system is outputing to another device that you
are not looking at. It could be very well going to the framebuffer,
thought it seems more likely it is going to netcon0. And I don't think
netcon0 is initialized at that point, so it is going to >/dev/null in
essence.

Add this to your command argument 'console=hvc0' for your guest.