Re: [Crash-utility] [PATCH 0/2] qemu: Parse necessary sections in crash added in qemu
----- Original Message -----
Qemu migration code added new sections to add features
for live migration of VM. For loading vmcore file captured
with 'virsh dump' we need to parse these sections in crash.
This series contains two patches, which parse these sections:
patch1: parse 'vm_configuration' section
patch2: parse 'vm_footer' section
qemu-load.c | 20 ++++++++++++++++++++
qemu-load.h | 4 +++-
2 files changed, 23 insertions(+), 1 deletion(-)
--
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Hi Pankaj,
I suppose I can take the patch. But, given the advent of "virsh dump
--memory-only"
back in 2012, and more recently, Oleg's added support for QEMU ramdumps by specifying
a memory-backend-file object to the qemu-kvm command:
commit 89ed9d0a7f7da4578294a492c1ad857244ce7352
Author: Dave Anderson <anderson(a)redhat.com>
Date: Wed May 4 11:50:19 2016 -0400
Introduction of support for "live" ramdump files, such as those that
are specified by the QEMU mem-path argument of a memory-backend-file
object. This allows the running of a live crash session against a
QEMU guest from the host machine. In this example, the /tmp/MEM file
on a QEMU host represents the guest's physical memory:
$ qemu-kvm ...other-options... \
-object memory-backend-file,id=MEM,size=128m,mem-path=/tmp/MEM,share=on \
-numa node,memdev=MEM -m 128
and a live session run can be run against the guest kernel like so:
$ crash <path-to-guest-vmlinux> live:/tmp/MEM@0
By prepending the ramdump image name with "live:", the crash session will
act as if it were running a normal live session.
(oleg(a)redhat.com)
And if the guest above crashed, the leftover file can be used as a regular
ramdump dumpfile:
commit 67a815b8749fbd5c99c29d24b4e699b1d618ddbf
Author: Dave Anderson <anderson(a)redhat.com>
Date: Wed May 4 14:34:53 2016 -0400
Added support for x86_64 ramdump files. Without the patch, the crash
session fails immediately with the message "ramdump: unsupported
machine type: X86_64".
(anderson(a)redhat.com)
So I don't know why anybody would ever want to use the old "kvmdump"
format?
It's for all practical purposes deprecated, not to mention that it's really
an unsuitable excuse for a crash dumpfile.
Dave