Re: [Xen-devel] bug: unable to LZ4 decompress ub1910 installer kernel when launching domU

[Jan Beulich <jbeulich@xxxxxxxx>]

On 01.12.2019 18:47, Jeremi Piotrowski wrote:
> On Thu, Oct 24, 2019 at 10:12:19AM +0200, Jan Beulich wrote:
>> On 23.10.2019 22:33, Pry Mar wrote:
>>> Hello xen-devel,
>>>
>>> https://paste.debian.net/plain/1109374
>>>
>>> shows my traces from a healthy CentOS 8, xen-4.12.1 dom0 when trying
>>> to launch a pv install of the newly released ub1910. The source is a
>>> block-attached ISO and the kernel/ramdisk was copied off locally.
>>
>> Would you please increase verbosity (xl -vvv create ...) such that we
>> can see what exactly the decompression code doesn't like about this
>> kernel image?
> 
> I stumbled across the same issue, below is the xl -vvvv create output.
> 
> Parsing config from ubuntu.cfg
> libxl: debug: libxl_create.c:1693:do_domain_create: Domain 0:ao 
> 0x55a598e77190: create: how=(nil) callback=(nil) poller=0x55a598e74040
> libxl: debug: libxl_device.c:397:libxl__device_disk_set_backend: Disk 
> vdev=xvda spec.backend=unknown
> libxl: debug: libxl_device.c:358:disk_try_backend: Disk vdev=xvda, backend 
> phy unsuitable due to format qcow2
> libxl: debug: libxl_device.c:431:libxl__device_disk_set_backend: Disk 
> vdev=xvda, using backend qdisk
> libxl: debug: libxl_create.c:1018:initiate_domain_create: Domain 11:running 
> bootloader
> libxl: debug: libxl_bootloader.c:334:libxl__bootloader_run: Domain 11:no 
> bootloader configured, using user supplied kernel
> libxl: debug: libxl_event.c:689:libxl__ev_xswatch_deregister: watch 
> w=0x55a598e827a8: deregister unregistered
> domainbuilder: detail: xc_dom_allocate: cmdline="", features=""
> libxl: debug: libxl_dom.c:799:libxl__build_pv: pv kernel mapped 0 path 
> /tank/xenscratch/ubuntu/vmlinuz-5.3.0-23-generic
> domainbuilder: detail: xc_dom_kernel_file: 
> filename="/tank/xenscratch/ubuntu/vmlinuz-5.3.0-23-generic"
> domainbuilder: detail: xc_dom_malloc_filemap    : 11132 kB
> domainbuilder: detail: xc_dom_boot_xen_init: ver 4.12, caps xen-3.0-x86_64 
> xen-3.0-x86_32p 
> domainbuilder: detail: xc_dom_parse_image: called
> domainbuilder: detail: xc_dom_find_loader: trying multiboot-binary loader ... 
> domainbuilder: detail: loader probe failed
> domainbuilder: detail: xc_dom_find_loader: trying HVM-generic loader ... 
> domainbuilder: detail: loader probe failed
> domainbuilder: detail: xc_dom_find_loader: trying Linux bzImage loader ... 
> domainbuilder: detail: LZ4 decompression error: decoding failed

This suggests that the decoding logic didn't like the input. Since as
per the other mail manual decompression works, this will likely need
debugging by someone able to repro.

Jan

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel