[PATCH] pv-grub: fix boot crash when no fb is available

[PATCH] pv-grub: fix boot crash when no fb is available

[Samuel Thibault]

pv-grub: fix boot crash when no fb is available

When no fb is available, init_fbfront will return, so the local
semaphore for synchronization with the kbd thread would get dropped.
Using a global static semaphore instead fixes this.

Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>

diff -r 8dada4c897c9 stubdom/grub/mini-os.c
--- a/stubdom/grub/mini-os.c	Sat Mar 06 13:31:42 2010 +0000
+++ b/stubdom/grub/mini-os.c	Sun Apr 04 19:13:06 2010 +0200
@@ -651,12 +651,11 @@
     return 0;
 }
 
+static DECLARE_MUTEX_LOCKED(kbd_sem);
 static void kbd_thread(void *p)
 {
-    struct semaphore *sem = p;
-
     kbd_dev = init_kbdfront(NULL, 1);
-    up(sem);
+    up(&kbd_sem);
 }
 
 struct fbfront_dev *fb_open(void *fb, int width, int height, int depth)
@@ -665,10 +664,9 @@
     int linesize = width * (depth / 8);
     int memsize = linesize * height;
     int numpages = (memsize + PAGE_SIZE - 1) / PAGE_SIZE;
-    DECLARE_MUTEX_LOCKED(sem);
     int i;
 
-    create_thread("kbdfront", kbd_thread, &sem);
+    create_thread("kbdfront", kbd_thread, &kbd_sem);
 
     mfns = malloc(numpages * sizeof(*mfns));
     for (i = 0; i < numpages; i++) {
@@ -681,7 +679,7 @@
     if (!fb_dev)
         return NULL;
 
-    down(&sem);
+    down(&kbd_sem);
     if (!kbd_dev)
         return NULL;

Re: [PATCH] pv-grub: fix boot crash when no fb is available

[David P. Quigley]

I applied this patch and the mini-os patch that arrived just before this
and neither of them seem to address my problem. It is still hanging with
the same output from xm create -c

Dave

Re: [PATCH] pv-grub: fix boot crash when no fb is available

[Samuel Thibault]

David P. Quigley, le Mon 05 Apr 2010 09:40:22 -0400, a écrit :
> I applied this patch and the mini-os patch that arrived just before this
> and neither of them seem to address my problem. It is still hanging with
> the same output from xm create -c

It is hanging?  I thought it was somehow crashing?  In any case, please
send the complete domain configuration file.

Samuel

Re: [PATCH] pv-grub: fix boot crash when no fb is available

[David P. Quigley]

[-- Attachment #1: Type: text/plain, Size: 652 bytes --]

On Mon, 2010-04-05 at 17:16 +0200, Samuel Thibault wrote:
> David P. Quigley, le Mon 05 Apr 2010 09:40:22 -0400, a écrit :
> > I applied this patch and the mini-os patch that arrived just before this
> > and neither of them seem to address my problem. It is still hanging with
> > the same output from xm create -c
> 
> It is hanging?  I thought it was somehow crashing?  In any case, please
> send the complete domain configuration file.
> 
> Samuel

I have attached my domU config. In my configuration I'm pretty sure it
is hanging because the domain is still running but is not responsive. I
have to xm destroy it to stop it.

Dave

[-- Attachment #2: domU-pv.conf --]
[-- Type: text/plain, Size: 14270 bytes --]

#  -*- mode: python; -*-
#============================================================================
# Python configuration setup for 'xm create'.
# This script sets the parameters used when a domain is created using 'xm create'.
# You use a separate script for each domain you want to create, or 
# you can set the parameters for the domain on the xm command line.
#============================================================================

#----------------------------------------------------------------------------
# Kernel image file.
# Boot kernel from host
#kernel = "/boot/vmlinuz-2.6.30.10-105.2.23.fc11.x86_64"
#ramdisk = "/boot/initrd-2.6.30.10-105.2.23.fc11.x86_64.img"
#
# Run grub within domain, boot from its boot partition.
kernel = "/usr/lib/xen/boot/pv-grub-x86_64.gz"
#extra = "(hd0,0)/boot/grub/menu.lst"
#
# Run pygrub to parse disk image and extract kernel.
#bootloader = "/usr/bin/pygrub"
#
# Boot kernel from host.
#kernel = "/boot/vmlinuz-2.6.32.9-xen"
#extra = "ro root=xvda2"

# The domain build function. HVM domain uses 'hvm'.
builder='linux'

# Initial memory allocation (in megabytes) for the new domain.
#
# WARNING: Creating a domain with insufficient memory may cause out of
#          memory errors. The domain needs enough memory to boot kernel
#          and modules. Allocating less than 32MBs is not recommended.
memory = 512

# Shadow pagetable memory for the domain, in MB.
# If not explicictly set, xend will pick an appropriate value.  
# Should be at least 2KB per MB of domain memory, plus a few MB per vcpu.
# shadow_memory = 8

# A name for your domain. All domains must have different names.
name = "SEHostStorage-PV"

access_control = ["policy=,label=system_u:object_r:domU_t" ]

# 128-bit UUID for the domain.  The default behavior is to generate a new UUID
# on each call to 'xm create'.
#uuid = "06ed00fe-1162-4fc4-b5d8-11993ee4a8b9"

#-----------------------------------------------------------------------------
# The number of cpus guest platform has, default=1
#vcpus=1

# Enable/disable HVM guest PAE, default=1 (enabled)
#pae=1

# Enable/disable HVM guest ACPI, default=1 (enabled)
#acpi=1

# Enable/disable HVM APIC mode, default=1 (enabled)
# Note that this option is ignored if vcpus > 1
#apic=1

# Enable/disable extended power management support within HVM guest, i.e., beyond
# S3, S4, S5 within guest like exposing battery meter.
# 0 (default option, extended power management support disabled)
# 1 (pass-through mode; uses pass-through as needed; efficient but limited in scope)
# 2 (non pass-through mode; extended scope, likely to work on all applicable environment
#    but comparitively less efficient than pass-through mode)
# xen_extended_power_mgmt=0

# List of which CPUS this domain is allowed to use, default Xen picks
#cpus = ""         # leave to Xen to pick
#cpus = "0"        # all vcpus run on CPU0
#cpus = "0-3,5,^1" # all vcpus run on cpus 0,2,3,5
#cpus = ["2", "3"] # VCPU0 runs on CPU2, VCPU1 runs on CPU3

# Optionally define mac and/or bridge for the network interfaces.
# Random MACs are assigned if not given.
#vif = [ 'type=ioemu, mac=00:16:3e:00:00:11, bridge=xenbr0, model=ne2k_pci' ]
# type=ioemu specify the NIC is an ioemu device not netfront
vif = [ 'type=ioemu, bridge=virbr0' ]

#----------------------------------------------------------------------------
# Define the disk devices you want the domain to have access to, and
# what you want them accessible as.
# Each disk entry is of the form phy:UNAME,DEV,MODE
# where UNAME is the device, DEV is the device name the domain will see,
# and MODE is r for read-only, w for read-write.

#disk = [ 'phy:hda1,hda1,r' ]
disk = [ 'tap:tapdisk:aio:/home/dpquigl/SEHostStorage/SEHostStorage-sda.raw,hda,w', ',hdc:cdrom,r' ]

#----------------------------------------------------------------------------
# Configure the behaviour when a domain exits.  There are three 'reasons'
# for a domain to stop: poweroff, reboot, and crash.  For each of these you
# may specify:
#
#   "destroy",        meaning that the domain is cleaned up as normal;
#   "restart",        meaning that a new domain is started in place of the old
#                     one;
#   "preserve",       meaning that no clean-up is done until the domain is
#                     manually destroyed (using xm destroy, for example); or
#   "rename-restart", meaning that the old domain is not cleaned up, but is
#                     renamed and a new domain started in its place.
#
# In the event a domain stops due to a crash, you have the additional options:
#
#   "coredump-destroy", meaning dump the crashed domain's core and then destroy;
#   "coredump-restart', meaning dump the crashed domain's core and the restart.
#
# The default is
#
#   on_poweroff = 'destroy'
#   on_reboot   = 'restart'
#   on_crash    = 'restart'
#
# For backwards compatibility we also support the deprecated option restart
#
# restart = 'onreboot' means on_poweroff = 'destroy'
#                            on_reboot   = 'restart'
#                            on_crash    = 'destroy'
#
# restart = 'always'   means on_poweroff = 'restart'
#                            on_reboot   = 'restart'
#                            on_crash    = 'restart'
#
# restart = 'never'    means on_poweroff = 'destroy'
#                            on_reboot   = 'destroy'
#                            on_crash    = 'destroy'

#on_poweroff = 'destroy'
#on_reboot   = 'restart'
#on_crash    = 'restart'

#============================================================================

# Device Model to be used
device_model = 'qemu-dm'

#-----------------------------------------------------------------------------
# boot on floppy (a), hard disk (c), Network (n) or CD-ROM (d) 
# default: hard disk, cd-rom, floppy
#boot="cda"

#-----------------------------------------------------------------------------
#  write to temporary files instead of disk image files
#snapshot=1

#----------------------------------------------------------------------------
# enable SDL library for graphics, default = 0
sdl=0

#----------------------------------------------------------------------------
# enable OpenGL for texture rendering inside the SDL window, default = 1
# valid only if sdl is enabled.
opengl=1

#----------------------------------------------------------------------------
# enable VNC library for graphics, default = 1
vnc=1

#----------------------------------------------------------------------------
# address that should be listened on for the VNC server if vnc is set.
# default is to use 'vnc-listen' setting from
# auxbin.xen_configdir() + /xend-config.sxp
#vnclisten="127.0.0.1"

#----------------------------------------------------------------------------
# set VNC display number, default = domid
#vncdisplay=1

#----------------------------------------------------------------------------
# try to find an unused port for the VNC server, default = 1
#vncunused=1

#----------------------------------------------------------------------------
# set password for domain's VNC console
# default is depents on vncpasswd in xend-config.sxp
vncpasswd=''

#----------------------------------------------------------------------------
# no graphics, use serial port
#nographic=0

#----------------------------------------------------------------------------
# enable stdvga, default = 0 (use cirrus logic device model)
stdvga=0

#-----------------------------------------------------------------------------
#   serial port re-direct to pty deivce, /dev/pts/n 
#   then xm console or minicom can connect
serial='pty'


#-----------------------------------------------------------------------------
#   Qemu Monitor, default is disable
#   Use ctrl-alt-2 to connect
#monitor=1


#-----------------------------------------------------------------------------
#   enable sound card support, [sb16|es1370|all|..,..], default none
#soundhw='sb16'


#-----------------------------------------------------------------------------
#    set the real time clock to local time [default=0 i.e. set to utc]
#localtime=1


#-----------------------------------------------------------------------------
#    set the real time clock offset in seconds [default=0 i.e. same as dom0]
#rtc_timeoffset=3600

#-----------------------------------------------------------------------------
#    start in full screen
#full-screen=1   


#-----------------------------------------------------------------------------
#   Enable USB support (specific devices specified at runtime through the
#			monitor window)
#usb=1

#   Enable USB mouse support (only enable one of the following, `mouse' for
#			      PS/2 protocol relative mouse, `tablet' for
#			      absolute mouse)
#usbdevice='mouse'
usbdevice='tablet'

#-----------------------------------------------------------------------------
#   Set keyboard layout, default is en-us keyboard. 
#keymap='ja'

#-----------------------------------------------------------------------------
#   Enable/disable xen platform PCI device, default=1 (enabled)
#xen_platform_pci=1

#-----------------------------------------------------------------------------
#   Configure guest CPUID responses:
#
#cpuid=[ '1:ecx=xxxxxxxxxxx00xxxxxxxxxxxxxxxxxxx,
#           eax=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx' ]
# - Unset the SSE4 features (CPUID.1[ECX][20-19])
# - Default behaviour for all other bits in ECX And EAX registers.
# 
# Each successive character represent a lesser-significant bit:
#  '1' -> force the corresponding bit to 1
#  '0' -> force to 0
#  'x' -> Get a safe value (pass through and mask with the default policy)
#  'k' -> pass through the host bit value
#  's' -> as 'k' but preserve across save/restore and migration
# 
#   Expose to the guest multi-core cpu instead of multiple processors
# Example for intel, expose a 8-core processor :
#cpuid=['1:edx=xxx1xxxxxxxxxxxxxxxxxxxxxxxxxxxx,
#          ebx=xxxxxxxx00010000xxxxxxxxxxxxxxxx',
#     '4,0:eax=001111xxxxxxxxxxxxxxxxxxxxxxxxxx']
#  - CPUID.1[EDX][HT] : Enable HT
#  - CPUID.1[EBX] : Number of vcpus * 2
#  - CPUID.4,0[EAX] : Number of vcpus * 2 - 1
#vcpus=8
#
# Example for amd, expose a 5-core processor :
# cpuid = ['1:ebx=xxxxxxxx00001010xxxxxxxxxxxxxxxx,
#             edx=xxx1xxxxxxxxxxxxxxxxxxxxxxxxxxxx',
# '0x80000001:ecx=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx1x',
# '0x80000008:ecx=xxxxxxxxxxxxxxxxxxxxxxxxxx001001']
#   - CPUID.1[EBX] : Threads per Core * Cores per Socket (2 * #vcpus)
#   - CPUID.1[EDX][HT] : Enable HT
#   - CPUID.0x80000001[CmpLegacy] : Use legacy method
#   - CPUID.0x80000008[ECX] : #vcpus * 2 - 1
#vcpus=5
#
#  Downgrade the cpuid to make a better compatibility for migration :
# Look like a generic 686 :
# cpuid = [ '0:eax=0x3,ebx=0x0,ecx=0x0,edx=0x0',
#           '1:eax=0x06b1,
#              ecx=xxxxxxxxxxx0000xx00xxx0000000xx0,
#              edx=xxx00000xxxxxxx0xxxxxxxxx0xxxxxx',
#           '4:eax=0x3,ebx=0x0,ecx=0x0,edx=0x0',
#  '0x80000000:eax=0x3,ebx=0x0,ecx=0x0,edx=0x0']
#  with the highest leaf
#  - CPUID.0[EAX] : Set the highest leaf
#  - CPUID.1[EAX] : 686 
#  - CPUID.1[ECX] : Mask some features
#  - CPUID.1[EDX] : Mask some features
#  - CPUID.4 : Reply like the highest leaf, in our case CPUID.3
#  - CPUID.0x80000000 : No extension we are on a Pentium III, reply like the
#  highest leaf (CPUID.3).
#
#   Configure host CPUID consistency checks, which must be satisfied for this
#   VM to be allowed to run on this host's processor type:
#cpuid_check=[ '1:ecx=xxxxxxxxxxxxxxxxxxxxxxxxxx1xxxxx' ]
# - Host must have VMX feature flag set
#
# The format is similar to the above for 'cpuid':
#  '1' -> the bit must be '1'
#  '0' -> the bit must be '0'
#  'x' -> we don't care (do not check)
#  's' -> the bit must be the same as on the host that started this VM

#-----------------------------------------------------------------------------
#   Configure passthrough PCI{,-X,e} devices:
#
#   pci=[ '[SSSS:]BB:DD.F[,option1[,option2[...]]]', ... ]
#
#   [SSSS]:BB:DD.F  "bus segment:bus:device.function"(1) of the device to
#                   be assigned, bus segment is optional. All fields are
#                   in hexadecimal and no field should be longer than that
#                   as shown in the pattern. Successful assignment may need
#                   certain hardware support and additional configurations
#                   (e.g. VT-d, see docs/misc/vtd.txt for more details).
#
#       (1) bus segment is sometimes also referred to as the PCI "domain",
#           not to be confused with Xen domain.
#
#
#   optionN         per-device options in "key=val" format. Current
#                   available options are:
#                   - msitranslate=0|1
#                      per-device overriden of pci_msitranslate, see below
#                   - power_mgmt=0|1
#                      per-device overriden of pci_power_mgmt, see below
#
#pci=[ '07:00.0', '07:00.1' ]

#   MSI-INTx translation for MSI capable devices:
#
#   If it's set, Xen will enable MSI for the device that supports it even
# if the guest don't use MSI. In the case, an IO-APIC type interrupt will
# be injected to the guest every time a corresponding MSI message is
# received.
#   If the guest enables MSI or MSI-X, the translation is automatically
# turned off.
# 
#pci_msitranslate=1

#   PCI Power Management:
#
#   If it's set, the guest OS will be able to program D0-D3hot states of the
# PCI device for the purpose of low power consumption.
# 
#pci_power_mgmt=0

#-----------------------------------------------------------------------------
#   Configure PVSCSI devices:
#
#vscsi=[ 'PDEV, VDEV' ]
#
#   PDEV   gives physical SCSI device to be attached to specified guest
#          domain by one of the following identifier format.
#          - XX:XX:XX:XX (4-tuples with decimal notation which shows
#                          "host:channel:target:lun")
#          - /dev/sdxx or sdx
#          - /dev/stxx or stx
#          - /dev/sgxx or sgx
#          - result of 'scsi_id -gu -s'.
#            ex. # scsi_id -gu -s /block/sdb
#                  36000b5d0006a0000006a0257004c0000
#
#   VDEV   gives virtual SCSI device by 4-tuples (XX:XX:XX:XX) as 
#          which the specified guest domain recognize.
#

#vscsi = [ '/dev/sdx, 0:0:0:0' ]

[-- Attachment #3: Type: text/plain, Size: 138 bytes --]

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Re: [PATCH] pv-grub: fix boot crash when no fb is available

[Samuel Thibault]

Hello,

David P. Quigley, le Mon 05 Apr 2010 11:17:32 -0400, a écrit :
> disk = [ 'tap:tapdisk:aio:/home/dpquigl/SEHostStorage/SEHostStorage-sda.raw,hda,w', ',hdc:cdrom,r' ]

This indeed hangs for me. Please try

disk = [ 'file:/home/dpquigl/SEHostStorage/SEHostStorage-sda.raw,hda,w' ]

Samuel

Re: [PATCH] pv-grub: fix boot crash when no fb is available

[David P. Quigley]

On Mon, 2010-04-05 at 23:57 +0200, Samuel Thibault wrote:
> Hello,
> 
> David P. Quigley, le Mon 05 Apr 2010 11:17:32 -0400, a écrit :
> > disk = [ 'tap:tapdisk:aio:/home/dpquigl/SEHostStorage/SEHostStorage-sda.raw,hda,w', ',hdc:cdrom,r' ]
> 
> This indeed hangs for me. Please try
> 
> disk = [ 'file:/home/dpquigl/SEHostStorage/SEHostStorage-sda.raw,hda,w' ]
> 
> Samuel

This did help. I've gotten to a grub prompt now. Apparently there is an
issue with blktap2 and pv-grub. I'm going to work on getting it to boot
with the new disk line then we can work on getting blktap2 to work
later.

Re: [PATCH] pv-grub: fix boot crash when no fb is available

[Jeremy Fitzhardinge]

On 04/06/2010 08:42 AM, David P. Quigley wrote:
> This did help. I've gotten to a grub prompt now. Apparently there is an
> issue with blktap2 and pv-grub. I'm going to work on getting it to boot
> with the new disk line then we can work on getting blktap2 to work
> later.
>    

I have no problem with blktap2 pvgrub, but my storage is a bit different:

    'tap:aio:/dev/vg_lilith-raid/xen-f13-64,xvda,w'

(no "tapdisk").  I'm not sure what the difference is.

     J

Re: [PATCH] pv-grub: fix boot crash when no fb is available

[David P. Quigley]

On Tue, 2010-04-06 at 11:16 -0700, Jeremy Fitzhardinge wrote:
> On 04/06/2010 08:42 AM, David P. Quigley wrote:
> > This did help. I've gotten to a grub prompt now. Apparently there is an
> > issue with blktap2 and pv-grub. I'm going to work on getting it to boot
> > with the new disk line then we can work on getting blktap2 to work
> > later.
> >    
> 
> I have no problem with blktap2 pvgrub, but my storage is a bit different:
> 
>     'tap:aio:/dev/vg_lilith-raid/xen-f13-64,xvda,w'
> 
> (no "tapdisk").  I'm not sure what the difference is.
> 
>      J

I'm under the impression that if you just do tap:aio it instantiates a
blktap device not a blktap2 device. There are definitely different
blktap controller classes in xend which handle entries using tapdisk and
ones just using tap.

Dave

Re: [PATCH] pv-grub: fix boot crash when no fb is available

[Jeremy Fitzhardinge]

On 04/06/2010 11:22 AM, David P. Quigley wrote:
> I'm under the impression that if you just do tap:aio it instantiates a
> blktap device not a blktap2 device. There are definitely different
> blktap controller classes in xend which handle entries using tapdisk and
> ones just using tap.
>    

The pvops dom0 doesn't have blktap support, only blktap2 (unless blktap2 
does a back-compat thing?).  Or maybe it falls back to plain blkback?

     J

Re: [PATCH] pv-grub: fix boot crash when no fb is available

[Samuel Thibault]

David P. Quigley, le Tue 06 Apr 2010 11:42:20 -0400, a écrit :
> On Mon, 2010-04-05 at 23:57 +0200, Samuel Thibault wrote:
> > David P. Quigley, le Mon 05 Apr 2010 11:17:32 -0400, a écrit :
> > > disk = [ 'tap:tapdisk:aio:/home/dpquigl/SEHostStorage/SEHostStorage-sda.raw,hda,w', ',hdc:cdrom,r' ]
> > 
> > This indeed hangs for me. Please try
> > 
> > disk = [ 'file:/home/dpquigl/SEHostStorage/SEHostStorage-sda.raw,hda,w' ]
> > 
> > Samuel
> 
> This did help. I've gotten to a grub prompt now.

Ok, cool.

> Apparently there is an issue with blktap2 and pv-grub.

Well, more precisely, with MiniOS :)

It seems like a xenbus protocol issue. I don't really have the time to
investigate further in the blktap2 code to know which end is behaving
badly (I do not even know where the PV part of it is).  What I do know
is that according to xenstore-ls, MiniOS says it's initialized, but
the backend seems stuck in the initwait state, I don't know what it is
waiting for.

Samuel

Re: [PATCH] pv-grub: fix boot crash when no fb is available

[Daniel Stodden]

On Tue, 2010-04-06 at 15:17 -0400, Jeremy Fitzhardinge wrote:
> On 04/06/2010 11:22 AM, David P. Quigley wrote:
> > I'm under the impression that if you just do tap:aio it instantiates a
> > blktap device not a blktap2 device. There are definitely different
> > blktap controller classes in xend which handle entries using tapdisk and
> > ones just using tap.
> >    
> 
> The pvops dom0 doesn't have blktap support, only blktap2 (unless blktap2 
> does a back-compat thing?).  

No blktap1, and no compat layer. It's all blkback instances sitting on a
blktap2 node, which provides a block device node.

The disk I'm running for development purposes is set up as follows:

disk = [ "tap:tapdisk:aio:/var/tmp/lenny.ext,xvda,w" ]

Took me a while to figure the syntax out, not sure if different ones
like yours work too.

> Or maybe it falls back to plain blkback?

Could be... What major number do you see in the physical-device XS node?

That config thing is clearly a nightmare.

Daniel

Re: Re: [PATCH] pv-grub: fix boot crash when no fb is available

[David P. Quigley]

On Tue, 2010-04-06 at 23:47 +0200, Samuel Thibault wrote:
> David P. Quigley, le Tue 06 Apr 2010 11:42:20 -0400, a écrit :
> > On Mon, 2010-04-05 at 23:57 +0200, Samuel Thibault wrote:
> > > David P. Quigley, le Mon 05 Apr 2010 11:17:32 -0400, a écrit :
> > > > disk = [ 'tap:tapdisk:aio:/home/dpquigl/SEHostStorage/SEHostStorage-sda.raw,hda,w', ',hdc:cdrom,r' ]
> > > 
> > > This indeed hangs for me. Please try
> > > 
> > > disk = [ 'file:/home/dpquigl/SEHostStorage/SEHostStorage-sda.raw,hda,w' ]
> > > 
> > > Samuel
> > 
> > This did help. I've gotten to a grub prompt now.
> 
> Ok, cool.
> 
> > Apparently there is an issue with blktap2 and pv-grub.
> 
> Well, more precisely, with MiniOS :)
> 
> It seems like a xenbus protocol issue. I don't really have the time to
> investigate further in the blktap2 code to know which end is behaving
> badly (I do not even know where the PV part of it is).  What I do know
> is that according to xenstore-ls, MiniOS says it's initialized, but
> the backend seems stuck in the initwait state, I don't know what it is
> waiting for.
> 
> Samuel
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xensource.com
> http://lists.xensource.com/xen-devel

I just returned from vacation and am working on this again and have run
into a new stumbling block. I managed to solve the booting to the grub
prompt issue (apparently pvgrub can't handle symlinks). The issue now
though is that my image that works fine as an HVM seems to hang. I've
pasted the output below. In there you can see that there is a call trace
for something xen related early on in the kernel boot process. I'm
unsure if this is related to some of the other pvgrub problems I've been
seeing on the list as of late.

Dave

# xm create -c domU-pv.conf 
/usr/lib64/python2.6/site-packages/xen/xm/group.py:23: DeprecationWarning: the sets module is deprecated
  from sets import Set
Using config file "./domU-pv.conf".
Started domain SEHostStorage-PV (id=9)
Xen Minimal OS!
  start_info: 0xaa6000(VA)
    nr_pages: 0x20000
  shared_inf: 0xbfa56000(MA)
     pt_base: 0xaa9000(VA)
nr_pt_frames: 0x9
    mfn_list: 0x9a6000(VA)
   mod_start: 0x0(VA)
     mod_len: 0
       flags: 0x0
    cmd_line: (hd0,0)/boot/grub/grub.conf
  stack:      0x965980-0x985980
MM: Init
      _text: 0x0(VA)
     _etext: 0x69794(VA)
   _erodata: 0x8f000(VA)
     _edata: 0x97ae0(VA)
stack start: 0x965980(VA)
       _end: 0x9a5f88(VA)
  start_pfn: ab5
    max_pfn: 20000
Mapping memory range 0xc00000 - 0x20000000
setting 0x0-0x8f000 readonly
skipped 0x1000
MM: Initialise page allocator for baf000(baf000)-20000000(20000000)
MM: done
Demand map pfns at 20001000-2020001000.
Heap resides at 2020002000-4020002000.
Initialising timer interface
Initialising console ... done.
gnttab_table mapped at 0x20001000.
Initialising scheduler
Thread "Idle": pointer: 0x2020002050, stack: 0xcc0000
Initialising xenbus
Thread "xenstore": pointer: 0x2020002800, stack: 0xcd0000
Dummy main: start_info=0x985a80
Thread "main": pointer: 0x2020002fb0, stack: 0xce0000
  Booting 'SEHostStorage (2.6.30.9-102.fc11.x86_64)'

root (hd0,0)
Error ENOENT when reading the backend path device/vkbd/0/backend
WARN: No handler for port 0 when unbinding
WARN: close_port (null) failed rc=-22. ignored
Thread "kbdfront" exited.
 Filesystem type is ext2fs, partition type 0x83
kernel /boot/vmlinuz-2.6.30.9-102.fc11.x86_64 ro root=/dev/sda1 acpi=force
initrd /boot/initrd-2.6.30.9-102.fc11.x86_64.img

close blk: backend=/local/domain/0/backend/vbd/9/768 node=device/vbd/768
Initializing cgroup subsys cpuset
Initializing cgroup subsys cpu
Linux version 2.6.30.9-102.fc11.x86_64 (mockbuild@x86-2.fedora.phx.redhat.com) (gcc version 4.4.1 20090725 (Red Hat 4.4.1-2) (GCC) ) #1 SMP Fri Dec 4 00:18:53 EST 2009
Command line: ro root=/dev/sda1 acpi=force
KERNEL supported cpus:
  Intel GenuineIntel
  AMD AuthenticAMD
  Centaur CentaurHauls
ACPI in unprivileged domain disabled
BIOS-provided physical RAM map:
 Xen: 0000000000000000 - 00000000000a0000 (usable)
 Xen: 00000000000a0000 - 0000000000100000 (reserved)
 Xen: 0000000000100000 - 0000000001f19000 (usable)
 Xen: 0000000001f19000 - 000000000201c000 (reserved)
 Xen: 000000000201c000 - 0000000020000000 (usable)
DMI not present or invalid.
last_pfn = 0x20000 max_arch_pfn = 0x100000000
init_memory_mapping: 0000000000000000-0000000020000000
RAMDISK: 01926000 - 01f19000
ACPI Error (tbxfroot-0219): A valid RSDP was not found [20090320]
No NUMA configuration found
Faking a node at 0000000000000000-0000000020000000
Bootmem setup node 0 0000000000000000-0000000020000000
  NODE_DATA [0000000000008000 - 000000000001cfff]
  bootmap [000000000001d000 -  0000000000020fff] pages 4
(6 early reservations) ==> bootmem [0000000000 - 0020000000]
  #0 [0000000000 - 0000001000]   BIOS data page ==> [0000000000 - 0000001000]
  #1 [000201c000 - 0002031000]   XEN PAGETABLES ==> [000201c000 - 0002031000]
  #2 [0000006000 - 0000008000]       TRAMPOLINE ==> [0000006000 - 0000008000]
  #3 [0001000000 - 00019051a0]    TEXT DATA BSS ==> [0001000000 - 00019051a0]
  #4 [0001926000 - 0001f19000]          RAMDISK ==> [0001926000 - 0001f19000]
  #5 [0000100000 - 00001ea000]          PGTABLE ==> [0000100000 - 00001ea000]
Zone PFN ranges:
  DMA      0x00000000 -> 0x00001000
  DMA32    0x00001000 -> 0x00100000
  Normal   0x00100000 -> 0x00100000
Movable zone start PFN for each node
early_node_map[3] active PFN ranges
    0: 0x00000000 -> 0x000000a0
    0: 0x00000100 -> 0x00001f19
    0: 0x0000201c -> 0x00020000
SMP: Allowing 1 CPUs, 0 hotplNR_CPUS:64 nr_cpumask_bits:64 nr_cpu_ids:1 nr_node_ids:1
PERCPU: Allocated 20 4k pages, static data 79584 bytes
Xen: using vcpu_info placement
Built 1 zonelists in Node order, mobility grouping on.  Total pages: 128688
Policy zone: DMA32
Kernel command line: ro root=/dev/sda1 acpi=force
Initializing CPU#0
------------[ cut here ]------------
WARNING: at arch/x86/xen/enlighten.c:482 cvt_gate_to_trap+0x86/0xbe() (Not tainted)
Modules linked in:
Pid: 0, comm: swapper Not tainted 2.6.30.9-102.fc11.x86_64 #1
Call Trace:
 [<ffffffff81049505>] warn_slowpath_common+0x84/0x9c
 [<ffffffff81049531>] warn_slowpath_null+0x14/0x16
 [<ffffffff8100aa70>] cvt_gate_to_trap+0x86/0xbe
 [<ffffffff8100ab00>] xen_convert_trap_info+0x58/0x8d
 [<ffffffff8100aef3>] xen_load_idt+0x4c/0x70
 [<ffffffff813d2bf8>] cpu_init+0x11f/0x2ff
 [<ffffffff8100ac30>] ? xen_write_idt_entry+0x46/0xa9
 [<ffffffff8169dde1>] trap_init+0x248/0x251
 [<ffffffff81699bcb>] start_kernel+0x222/0x3f5
 [<ffffffff816992c1>] x86_64_start_reservations+0xac/0xb0
 [<ffffffff8169cc19>] xen_start_kernel+0x4ae/0x4b2
---[ end trace a7919e7f17c0a725 ]---
NR_IRQS:4352 nr_irqs:256
PID hash table entries: 2048 (order: 11, 16384 bytes)
Detected 2992.548 MHz processor.
Console: colour dummy device 80x25
console [tty0] enabled
console [hvc0] enabled
allocated 5242880 bytes of page_cgroup
please try cgroup_disable=memory option if you don't want
Checking aperture...
No AGP bridge found
Memory: 493924k/524288k available (3972k kernel code, 1420k absent, 28944k reserved, 2497k data, 1292k init)
SLUB: Genslabs=14, HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
installing Xen timer for CPU 0
Calibrating delay loop (skipped), value calculated using timer frequency.. 5985.09 BogoMIPS (lpj=2992548)
Security Framework initialized
SELinux:  Initializing.
Dentry cache hash table entries: 65536 (order: 7, 524288 bytes)
Inode-cache hash table entries: 32768 (order: 6, 262144 bytes)
Mount-cache hash table entries: 256
Initializing cgroup subsys ns
Initializing cgroup subsys cpuacct
Initializing cgroup subsys memory
Initializing cgroup subsys devices
Initializing cgroup subsys freezer
Initializing cgroup subsys net_cls
CPU: L1 I cache: 32K, L1 D cache: 32K
CPU: L2 cache: 6144K
CPU 0/0x0 -> Node 0
CPU: Unsupported number of siblings 4<6>SMP alternatives: switching to UP code
Freeing SMP alternatives: 31k freed
ftrace: converting mcount calls to 0f 1f 44 00 00
ftrace: allocating 19364 entries in 76 pages
Failed to register trace ftrace module notifier
Brought up 1 CPUs
net_namespace: 1952 bytes
Booting paravirtualized kernel on Xen
Xen version: 4.0.0-rc9 (preserve-AD)
Grant table initialized
regulator: core version 0.5
Time: 165:165:165  Date: 165/165/65
NET: Registered protocol family 16
PCI: Fatal: No config space access function found
bio: create slab <bio-0> at 0
ACPI: Interpreter disabled.
xen_balloon: Initialising balloon driver.
SCSI subsystem initialized
usbcore: registered new interface driver usbfs
usbcore: registered new interface driver hub
usbcore: registered new device driver usb
PCI: System does not support PCI
PCI: System does not support PCI
NetLabel: Initializing
NetLabel:  domain hash size = 128
NetLabel:  protocols = UNLABELED CIPSOv4
NetLabel:  unlabeled traffic allowed by default
pnp: PnP ACPI: disabled
NET: Registered protocol family 2
IP route cache hash table entries: 16384 (order: 5, 131072 bytes)
TCP established hash table entries: 65536 (order: 8, 1048576 bytes)
TCP bind hash table entries: 65536 (order: 8, 1048576 bytes)
TCP: Hash tables configured (established 65536 bind 65536)
TCP reno registered
NET: Registered protocol family 1
Trying to unpack rootfs image as initramfs...
Freeing initrd memory: 6092k freed
platform rtc_cmos: registered platform RTC device (no PNP device found)
audit: initializing netlink socket (disabled)
type=2000 audit(1271169982.263:1): initialized
HugeTLB registered 2 MB page size, pre-allocated 0 pages
VFS: Disk quotas dquot_6.5.2
Dquot-cache hash table entries: 512 (order 0, 4096 bytes)
msgmni has been set to 1035
alg: No test for stdrng (krng)
Block layer SCSI generic (bsg) driver version 0.4 loaded (major 252)
io scheduler noop registered
io scheduler anticipatory registered
io scheduler deadline registered
io scheduler cfq registered (default)
pci_hotplug: PCI Hot Plug PCI Core version: 0.5
pciehp: PCI Express Hot Plug Controller Driver version: 0.4
acpiphp: ACPI Hot Plug PCI Controller Driver version: 0.5
Non-volatile memory driver v1.3
Linux agpgart interface v0.103
Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
brd: module loaded
loop: module loaded
input: Macintosh mouse button emulation as /devices/virtual/input/input0
Driver 'sd' needs updating - please use bus_type methods
Driver 'sr' needs updating - please use bus_type methoMounting proc filesystem
Mounting sysfs filesystem
Creating /dev
Creating initial device nodes
Fusion MPT base driver 3.04.07
Copyright (c) 1999-2008 LSI Corporation
Fusion MPT SPI Host driver 3.04.07

Re: Re: [PATCH] pv-grub: fix boot crash when no fb is available

[Keir Fraser]

On 13/04/2010 15:55, "David P. Quigley" <dpquigl@tycho.nsa.gov> wrote:

> I just returned from vacation and am working on this again and have run
> into a new stumbling block. I managed to solve the booting to the grub
> prompt issue (apparently pvgrub can't handle symlinks). The issue now
> though is that my image that works fine as an HVM seems to hang. I've
> pasted the output below. In there you can see that there is a call trace
> for something xen related early on in the kernel boot process. I'm
> unsure if this is related to some of the other pvgrub problems I've been
> seeing on the list as of late.

Can you boot this kernel *without* using pvgrub or pygrub? The kernel's PV
support may well simply be buggy.

 -- Keir

Re: Re: [PATCH] pv-grub: fix boot crash when no fb is available

[Jeremy Fitzhardinge]

On 04/13/2010 07:55 AM, David P. Quigley wrote:
> I just returned from vacation and am working on this again and have run
> into a new stumbling block. I managed to solve the booting to the grub
> prompt issue (apparently pvgrub can't handle symlinks). The issue now
> though is that my image that works fine as an HVM seems to hang. I've
> pasted the output below. In there you can see that there is a call trace
> for something xen related early on in the kernel boot process. I'm
> unsure if this is related to some of the other pvgrub problems I've been
> seeing on the list as of late.
>   

Are you using stubdoms?  One of Samuel's patches caused hvm+stubdom
domains to not start for me (however, they really didn't start, so your
case doesn't look exactly the same).

    J

> Dave
>
> # xm create -c domU-pv.conf 
> /usr/lib64/python2.6/site-packages/xen/xm/group.py:23: DeprecationWarning: the sets module is deprecated
>   from sets import Set
> Using config file "./domU-pv.conf".
> Started domain SEHostStorage-PV (id=9)
> Xen Minimal OS!
>   start_info: 0xaa6000(VA)
>     nr_pages: 0x20000
>   shared_inf: 0xbfa56000(MA)
>      pt_base: 0xaa9000(VA)
> nr_pt_frames: 0x9
>     mfn_list: 0x9a6000(VA)
>    mod_start: 0x0(VA)
>      mod_len: 0
>        flags: 0x0
>     cmd_line: (hd0,0)/boot/grub/grub.conf
>   stack:      0x965980-0x985980
> MM: Init
>       _text: 0x0(VA)
>      _etext: 0x69794(VA)
>    _erodata: 0x8f000(VA)
>      _edata: 0x97ae0(VA)
> stack start: 0x965980(VA)
>        _end: 0x9a5f88(VA)
>   start_pfn: ab5
>     max_pfn: 20000
> Mapping memory range 0xc00000 - 0x20000000
> setting 0x0-0x8f000 readonly
> skipped 0x1000
> MM: Initialise page allocator for baf000(baf000)-20000000(20000000)
> MM: done
> Demand map pfns at 20001000-2020001000.
> Heap resides at 2020002000-4020002000.
> Initialising timer interface
> Initialising console ... done.
> gnttab_table mapped at 0x20001000.
> Initialising scheduler
> Thread "Idle": pointer: 0x2020002050, stack: 0xcc0000
> Initialising xenbus
> Thread "xenstore": pointer: 0x2020002800, stack: 0xcd0000
> Dummy main: start_info=0x985a80
> Thread "main": pointer: 0x2020002fb0, stack: 0xce0000
>   Booting 'SEHostStorage (2.6.30.9-102.fc11.x86_64)'
>
> root (hd0,0)
> Error ENOENT when reading the backend path device/vkbd/0/backend
> WARN: No handler for port 0 when unbinding
> WARN: close_port (null) failed rc=-22. ignored
> Thread "kbdfront" exited.
>  Filesystem type is ext2fs, partition type 0x83
> kernel /boot/vmlinuz-2.6.30.9-102.fc11.x86_64 ro root=/dev/sda1 acpi=force
> initrd /boot/initrd-2.6.30.9-102.fc11.x86_64.img
>
> close blk: backend=/local/domain/0/backend/vbd/9/768 node=device/vbd/768
> Initializing cgroup subsys cpuset
> Initializing cgroup subsys cpu
> Linux version 2.6.30.9-102.fc11.x86_64 (mockbuild@x86-2.fedora.phx.redhat.com) (gcc version 4.4.1 20090725 (Red Hat 4.4.1-2) (GCC) ) #1 SMP Fri Dec 4 00:18:53 EST 2009
> Command line: ro root=/dev/sda1 acpi=force
> KERNEL supported cpus:
>   Intel GenuineIntel
>   AMD AuthenticAMD
>   Centaur CentaurHauls
> ACPI in unprivileged domain disabled
> BIOS-provided physical RAM map:
>  Xen: 0000000000000000 - 00000000000a0000 (usable)
>  Xen: 00000000000a0000 - 0000000000100000 (reserved)
>  Xen: 0000000000100000 - 0000000001f19000 (usable)
>  Xen: 0000000001f19000 - 000000000201c000 (reserved)
>  Xen: 000000000201c000 - 0000000020000000 (usable)
> DMI not present or invalid.
> last_pfn = 0x20000 max_arch_pfn = 0x100000000
> init_memory_mapping: 0000000000000000-0000000020000000
> RAMDISK: 01926000 - 01f19000
> ACPI Error (tbxfroot-0219): A valid RSDP was not found [20090320]
> No NUMA configuration found
> Faking a node at 0000000000000000-0000000020000000
> Bootmem setup node 0 0000000000000000-0000000020000000
>   NODE_DATA [0000000000008000 - 000000000001cfff]
>   bootmap [000000000001d000 -  0000000000020fff] pages 4
> (6 early reservations) ==> bootmem [0000000000 - 0020000000]
>   #0 [0000000000 - 0000001000]   BIOS data page ==> [0000000000 - 0000001000]
>   #1 [000201c000 - 0002031000]   XEN PAGETABLES ==> [000201c000 - 0002031000]
>   #2 [0000006000 - 0000008000]       TRAMPOLINE ==> [0000006000 - 0000008000]
>   #3 [0001000000 - 00019051a0]    TEXT DATA BSS ==> [0001000000 - 00019051a0]
>   #4 [0001926000 - 0001f19000]          RAMDISK ==> [0001926000 - 0001f19000]
>   #5 [0000100000 - 00001ea000]          PGTABLE ==> [0000100000 - 00001ea000]
> Zone PFN ranges:
>   DMA      0x00000000 -> 0x00001000
>   DMA32    0x00001000 -> 0x00100000
>   Normal   0x00100000 -> 0x00100000
> Movable zone start PFN for each node
> early_node_map[3] active PFN ranges
>     0: 0x00000000 -> 0x000000a0
>     0: 0x00000100 -> 0x00001f19
>     0: 0x0000201c -> 0x00020000
> SMP: Allowing 1 CPUs, 0 hotplNR_CPUS:64 nr_cpumask_bits:64 nr_cpu_ids:1 nr_node_ids:1
> PERCPU: Allocated 20 4k pages, static data 79584 bytes
> Xen: using vcpu_info placement
> Built 1 zonelists in Node order, mobility grouping on.  Total pages: 128688
> Policy zone: DMA32
> Kernel command line: ro root=/dev/sda1 acpi=force
> Initializing CPU#0
> ------------[ cut here ]------------
> WARNING: at arch/x86/xen/enlighten.c:482 cvt_gate_to_trap+0x86/0xbe() (Not tainted)
> Modules linked in:
> Pid: 0, comm: swapper Not tainted 2.6.30.9-102.fc11.x86_64 #1
> Call Trace:
>  [<ffffffff81049505>] warn_slowpath_common+0x84/0x9c
>  [<ffffffff81049531>] warn_slowpath_null+0x14/0x16
>  [<ffffffff8100aa70>] cvt_gate_to_trap+0x86/0xbe
>  [<ffffffff8100ab00>] xen_convert_trap_info+0x58/0x8d
>  [<ffffffff8100aef3>] xen_load_idt+0x4c/0x70
>  [<ffffffff813d2bf8>] cpu_init+0x11f/0x2ff
>  [<ffffffff8100ac30>] ? xen_write_idt_entry+0x46/0xa9
>  [<ffffffff8169dde1>] trap_init+0x248/0x251
>  [<ffffffff81699bcb>] start_kernel+0x222/0x3f5
>  [<ffffffff816992c1>] x86_64_start_reservations+0xac/0xb0
>  [<ffffffff8169cc19>] xen_start_kernel+0x4ae/0x4b2
> ---[ end trace a7919e7f17c0a725 ]---
> NR_IRQS:4352 nr_irqs:256
> PID hash table entries: 2048 (order: 11, 16384 bytes)
> Detected 2992.548 MHz processor.
> Console: colour dummy device 80x25
> console [tty0] enabled
> console [hvc0] enabled
> allocated 5242880 bytes of page_cgroup
> please try cgroup_disable=memory option if you don't want
> Checking aperture...
> No AGP bridge found
> Memory: 493924k/524288k available (3972k kernel code, 1420k absent, 28944k reserved, 2497k data, 1292k init)
> SLUB: Genslabs=14, HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
> installing Xen timer for CPU 0
> Calibrating delay loop (skipped), value calculated using timer frequency.. 5985.09 BogoMIPS (lpj=2992548)
> Security Framework initialized
> SELinux:  Initializing.
> Dentry cache hash table entries: 65536 (order: 7, 524288 bytes)
> Inode-cache hash table entries: 32768 (order: 6, 262144 bytes)
> Mount-cache hash table entries: 256
> Initializing cgroup subsys ns
> Initializing cgroup subsys cpuacct
> Initializing cgroup subsys memory
> Initializing cgroup subsys devices
> Initializing cgroup subsys freezer
> Initializing cgroup subsys net_cls
> CPU: L1 I cache: 32K, L1 D cache: 32K
> CPU: L2 cache: 6144K
> CPU 0/0x0 -> Node 0
> CPU: Unsupported number of siblings 4<6>SMP alternatives: switching to UP code
> Freeing SMP alternatives: 31k freed
> ftrace: converting mcount calls to 0f 1f 44 00 00
> ftrace: allocating 19364 entries in 76 pages
> Failed to register trace ftrace module notifier
> Brought up 1 CPUs
> net_namespace: 1952 bytes
> Booting paravirtualized kernel on Xen
> Xen version: 4.0.0-rc9 (preserve-AD)
> Grant table initialized
> regulator: core version 0.5
> Time: 165:165:165  Date: 165/165/65
> NET: Registered protocol family 16
> PCI: Fatal: No config space access function found
> bio: create slab <bio-0> at 0
> ACPI: Interpreter disabled.
> xen_balloon: Initialising balloon driver.
> SCSI subsystem initialized
> usbcore: registered new interface driver usbfs
> usbcore: registered new interface driver hub
> usbcore: registered new device driver usb
> PCI: System does not support PCI
> PCI: System does not support PCI
> NetLabel: Initializing
> NetLabel:  domain hash size = 128
> NetLabel:  protocols = UNLABELED CIPSOv4
> NetLabel:  unlabeled traffic allowed by default
> pnp: PnP ACPI: disabled
> NET: Registered protocol family 2
> IP route cache hash table entries: 16384 (order: 5, 131072 bytes)
> TCP established hash table entries: 65536 (order: 8, 1048576 bytes)
> TCP bind hash table entries: 65536 (order: 8, 1048576 bytes)
> TCP: Hash tables configured (established 65536 bind 65536)
> TCP reno registered
> NET: Registered protocol family 1
> Trying to unpack rootfs image as initramfs...
> Freeing initrd memory: 6092k freed
> platform rtc_cmos: registered platform RTC device (no PNP device found)
> audit: initializing netlink socket (disabled)
> type=2000 audit(1271169982.263:1): initialized
> HugeTLB registered 2 MB page size, pre-allocated 0 pages
> VFS: Disk quotas dquot_6.5.2
> Dquot-cache hash table entries: 512 (order 0, 4096 bytes)
> msgmni has been set to 1035
> alg: No test for stdrng (krng)
> Block layer SCSI generic (bsg) driver version 0.4 loaded (major 252)
> io scheduler noop registered
> io scheduler anticipatory registered
> io scheduler deadline registered
> io scheduler cfq registered (default)
> pci_hotplug: PCI Hot Plug PCI Core version: 0.5
> pciehp: PCI Express Hot Plug Controller Driver version: 0.4
> acpiphp: ACPI Hot Plug PCI Controller Driver version: 0.5
> Non-volatile memory driver v1.3
> Linux agpgart interface v0.103
> Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
> brd: module loaded
> loop: module loaded
> input: Macintosh mouse button emulation as /devices/virtual/input/input0
> Driver 'sd' needs updating - please use bus_type methods
> Driver 'sr' needs updating - please use bus_type methoMounting proc filesystem
> Mounting sysfs filesystem
> Creating /dev
> Creating initial device nodes
> Fusion MPT base driver 3.04.07
> Copyright (c) 1999-2008 LSI Corporation
> Fusion MPT SPI Host driver 3.04.07
>
>
>   

Re: Re: [PATCH] pv-grub: fix boot crash when no fb is available

[Samuel Thibault]

Hello,

You should perhaps test again with the
83fe79c0225f pv-grub: Fix for incorrect dom->p2m_host[] list
initialization
fix, as it could very be a culprit.

Samuel