Can't boot XZ compressed kernels in domU

SUSE Product Topics SLES Virtualization
1

Hello,

i am unable to boot Kernels in domU which are XZ compressed. In my special case i am able to boot debian xen-netboot kernels+initrd from wheezy (stable) where the kernel still ist compressed via gzip, but not debian jessie (testing/RC1) with a xz-compressed kernel.

Here is what i do:

Running dom0
SUSE Linux Enterprise Server 11 (x86_64)
VERSION = 11
PATCHLEVEL = 3

xen+xen-tools:

Repository: SUSE-Linux-Enterprise-Server-11-SP3 updates
Name: xen
Version: 4.2.5_02-0.7.1

Minimal domU installer configuration:

[CODE]kernel = “/tmp/vmlinuz”
ramdisk = “/tmp/initrd.gz”
extra = “debian-installer/exit/always_halt=true – quiet console=hvc0”
memory = 1024

name = “lxvm193-177”
vif = [‘mac=00:50:56:31:C1:B1,bridge=brintern-nsd’]
disk = [‘phy:/dev/server/lxvm193-177.xvda,xvda,w’][/CODE]

Working kernel+initrd

cd /tmp wget http://cdn.debian.net/debian/dists/wheezy/main/installer-amd64/current/images/netboot/xen/initrd.gz wget http://cdn.debian.net/debian/dists/wheezy/main/installer-amd64/current/images/netboot/xen/vmlinuz

[COLOR="#B22222"]Not working kernel+initrd[/COLOR]

wget http://cdn.debian.net/debian/dists/jessie/main/installer-amd64/current/images/netboot/xen/initrd.gz wget http://cdn.debian.net/debian/dists/jessie/main/installer-amd64/current/images/netboot/xen/vmlinuz

I got the following error messages:

# xm create lxvm193-177 -c Using config file "/etc/xen/vm/lxvm193-177". Error: (2, 'Invalid kernel', 'panic: xc_dom_core.c:638: xc_dom_find_loader: no loader found')

/var/log/xen/domain-builder-ng.log

2015-02-10 12:01:46 CET [20976] domainbuilder: detail: xc_dom_allocate: cmdline="", features="" 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: xc_dom_kernel_file: filename="/tmp/vmlinuz" 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: xc_dom_malloc_filemap : 3031 kB 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: xc_dom_parse_image: called 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: xc_dom_find_loader: trying ELF-generic loader ... 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: loader probe failed 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: xc_dom_find_loader: trying Linux bzImage loader ... 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: xc_try_xz_decode: XZ decompress support unavailable 2015-02-10 12:01:46 CET [20976] xc: error: panic: xc_dom_bzimageloader.c:699: xc_dom_probe_bzimage_kernel unable to XZ decompress kernel: Invalid kernel 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: loader probe failed 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: xc_dom_find_loader: trying multiboot-binary loader ... 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: loader probe failed 2015-02-10 12:01:46 CET [20976] xc: error: panic: xc_dom_core.c:638: xc_dom_find_loader: no loader found: Invalid kernel 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: xc_dom_release: called 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: xc_dom_allocate: cmdline="", features="" 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: xc_dom_kernel_file: filename="/tmp/vmlinuz" 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: xc_dom_malloc_filemap : 3031 kB 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: xc_dom_ramdisk_file: filename="/tmp/initrd.gz" 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: xc_dom_malloc_filemap : 32 MB 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: xc_dom_boot_xen_init: ver 4.2, caps xen-3.0-x86_64 xen-3.0-x86_32p hvm-3.0-x86_32 hvm-3.0-x86_32p hvm-3.0-x86_64 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: xc_dom_parse_image: called 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: xc_dom_find_loader: trying ELF-generic loader ... 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: loader probe failed 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: xc_dom_find_loader: trying Linux bzImage loader ... 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: xc_try_xz_decode: XZ decompress support unavailable 2015-02-10 12:01:46 CET [20976] xc: error: panic: xc_dom_bzimageloader.c:699: xc_dom_probe_bzimage_kernel unable to XZ decompress kernel: Invalid kernel 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: loader probe failed 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: xc_dom_find_loader: trying multiboot-binary loader ... 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: loader probe failed 2015-02-10 12:01:46 CET [20976] xc: error: panic: xc_dom_core.c:638: xc_dom_find_loader: no loader found: Invalid kernel 2015-02-10 12:01:46 CET [20976] domainbuilder: detail: xc_dom_release: called

/var/log/xen/xend.log:

[2015-02-10 12:01:46 20976] DEBUG (XendDomainInfo:103) XendDomainInfo.create(['vm', ['name', 'lxvm193-177'], ['memory', 1024], ['on_xend _start', 'ignore'], ['on_xend_stop', 'ignore'], ['vcpus', 1], ['oos', 1], ['image', ['linux', ['kernel', '/tmp/vmlinuz'], ['ramdisk', '/ tmp/initrd.gz'], ['videoram', 4], ['tsc_mode', 0], ['nomigrate', 0]]], ['s3_integrity', 1], ['device', ['vbd', ['uname', 'phy:/dev/serve r/lxvm193-177.xvda'], ['dev', 'xvda'], ['mode', 'w']]], ['device', ['vif', ['bridge', 'brintern-nsd'], ['mac', '00:50:56:31:C1:B1']]]]) [2015-02-10 12:01:46 20976] DEBUG (XendDomainInfo:2620) XendDomainInfo.constructDomain [2015-02-10 12:01:46 20976] DEBUG (balloon:206) Balloon: 1060192 KiB free; need 16384; done. [2015-02-10 12:01:46 20976] DEBUG (XendDomain:476) Adding Domain: 47 [2015-02-10 12:01:46 20976] DEBUG (XendDomainInfo:2966) XendDomainInfo.initDomain: 47 256 [2015-02-10 12:01:46 20976] DEBUG (XendDomainInfo:2993) _initDomain:shadow_memory=0x0, memory_static_max=0x40000000, memory_static_min=0 x0. [2015-02-10 12:01:46 20976] INFO (image:188) buildDomain os=linux dom=47 vcpus=1 [2015-02-10 12:01:46 20976] DEBUG (image:808) domid = 47 [2015-02-10 12:01:46 20976] DEBUG (image:809) memsize = 1024 [2015-02-10 12:01:46 20976] DEBUG (image:810) image = /tmp/vmlinuz [2015-02-10 12:01:46 20976] DEBUG (image:811) store_evtchn = 1 [2015-02-10 12:01:46 20976] DEBUG (image:812) console_evtchn = 2 [2015-02-10 12:01:46 20976] DEBUG (image:813) cmdline = [2015-02-10 12:01:46 20976] DEBUG (image:814) ramdisk = /tmp/initrd.gz [2015-02-10 12:01:46 20976] DEBUG (image:815) vcpus = 1 [2015-02-10 12:01:46 20976] DEBUG (image:816) features = [2015-02-10 12:01:46 20976] DEBUG (image:817) flags = 0 [2015-02-10 12:01:46 20976] DEBUG (image:818) superpages = 0 [2015-02-10 12:01:46 20976] ERROR (XendDomainInfo:3060) XendDomainInfo.initDomain: exception occurred Traceback (most recent call last): File "/usr/lib64/python2.6/site-packages/xen/xend/XendDomainInfo.py", line 3028, in _initDomain channel_details = self.image.createImage() File "/usr/lib64/python2.6/site-packages/xen/xend/image.py", line 171, in createImage return self.createDomain() File "/usr/lib64/python2.6/site-packages/xen/xend/image.py", line 190, in createDomain result = self.buildDomain() File "/usr/lib64/python2.6/site-packages/xen/xend/image.py", line 1205, in buildDomain rc = LinuxImageHandler.buildDomain(self) File "/usr/lib64/python2.6/site-packages/xen/xend/image.py", line 832, in buildDomain superpages = self.superpages) Error: (2, 'Invalid kernel', 'panic: xc_dom_core.c:638: xc_dom_find_loader: no loader found') [2015-02-10 12:01:46 20976] ERROR (XendDomainInfo:515) VM start failed Traceback (most recent call last): File "/usr/lib64/python2.6/site-packages/xen/xend/XendDomainInfo.py", line 501, in start XendTask.log_progress(31, 60, self._initDomain) File "/usr/lib64/python2.6/site-packages/xen/xend/XendTask.py", line 209, in log_progress retval = func(*args, **kwds) File "/usr/lib64/python2.6/site-packages/xen/xend/XendDomainInfo.py", line 3063, in _initDomain raise VmError(str(exn)) VmError: (2, 'Invalid kernel', 'panic: xc_dom_core.c:638: xc_dom_find_loader: no loader found') [2015-02-10 12:01:46 20976] DEBUG (XendDomainInfo:3213) XendDomainInfo.destroy: domid=47 [2015-02-10 12:01:46 20976] DEBUG (XendDomainInfo:2523) Destroying device model [2015-02-10 12:01:46 20976] DEBUG (XendDomainInfo:2530) Releasing devices [2015-02-10 12:01:46 20976] ERROR (XendDomainInfo:108) Domain construction failed Traceback (most recent call last): File "/usr/lib64/python2.6/site-packages/xen/xend/XendDomainInfo.py", line 106, in create vm.start() File "/usr/lib64/python2.6/site-packages/xen/xend/XendDomainInfo.py", line 501, in start XendTask.log_progress(31, 60, self._initDomain) File "/usr/lib64/python2.6/site-packages/xen/xend/XendTask.py", line 209, in log_progress retval = func(*args, **kwds) File "/usr/lib64/python2.6/site-packages/xen/xend/XendDomainInfo.py", line 3063, in _initDomain raise VmError(str(exn)) VmError: (2, 'Invalid kernel', 'panic: xc_dom_core.c:638: xc_dom_find_loader: no loader found')

At this point i am a bit puzzled, because xen should be able to decompress xz as stated here: http://wiki.xen.org/wiki/Archived/Kernel.org_Linux_on_Xen:

[QUOTE]Xen 3.4.2 and newer versions do have support for BZIP2 and LZMA compressed PV domU/guest kernels, assuming the required bzip2 and lzma (xz) libraries and development headers have been available at the Xen compilation time.
[/QUOTE]

I cannot imagine that the Suse build environment is lacking headers for xz, nor that this feature ist not compiled in by a builld-flag. Does anyone has a clue whats going on here? Am i missing something?

Thanks for any help

Lennart

2

Hi Lennart,

I’m having this checked and will report back as soon as possible.

Regards,
Jens

3

Hi Lennart,

this issue would severely benefit from running it through the official channels - are you in a position to open a service request with SUSE and send me (via PM) the SR number?

Best regards,
Jens