1.1.1 -> 1.1.2 migrate /managedsave issue

Commit Message

Philipp Hahn Oct. 24, 2012, 6:59 a.m. UTC

Hello Doug,

On Tuesday 23 October 2012 22:38:47 Doug Goldstein wrote:
> >>> qemu: warning: error while loading state for instance 0x0 of device
> >>> 'ram' load of migration failed
...
> >> I diagnosed that using gdb to single step kvm until I found
> >> hw/pci.c#get_pci_config_device() returning -EINVAL.
...
> But yes I can confirm that
> vmstate_load_state() which is calling field->info->get() which is
> calling get_pci_config_device() is returning -EINVAL.
...
> Any recommendations to fix this? Or do I need to kill the saved state
> and start over?

For start try to re-get the old PXE ROM files, that is for Debian re-install 
the old etherboot-qemu or an older Version of the ipxe-qemu package. If that 
then works again, you can go further. Otherwise you need to get the exact 
index "i" where get_pci_config_device() returns -EINVAL and match that with 
the PCI spec. For short see hw/pci_regs.h.


For our Debian based UCS distribution I patched qemu(-kvm) to use the old 
image files (which are still available and installed in parallel to the new 
files) if the pc-level is 0.14 or lower (which is the version we currently 
ship; only our next release will switch to 1.1.2).

I've attached my patch FYI. That is only a work around until QEMU provides a 
real solution. If you've used an e1000, that is not enougth because some more 
PCI configuration bits (PCI_STATUS_CAP_LIST) were changed in an incompatible 
way.

If I remember correctly there was a different bug report, where changed PCI 
bits were also responsible for breaking saved states: Some PCI devices were 
changed to multi-function devices (or the other way around), which also 
breaks loading of previous saved stated. I think it was a bug in libvirt 
which started adding an explicit "multifunction=on", while the save was done 
using an implicit "multifinction=off". 
(<https://forge.univention.org/bugzilla/show_bug.cgi?id=22877#c6> in our 
German BZ)

Sincerely
Philipp Hahn

Patch

diff -urN qemu-kvm-1.1.2+dfsg.orig/debian/patches/romfile-compatibility.diff qemu-kvm-1.1.2+dfsg/debian/patches/romfile-compatibility.diff
--- qemu-kvm-1.1.2+dfsg.orig/debian/patches/romfile-compatibility.diff	1970-01-01 01:00:00.000000000 +0100
+++ qemu-kvm-1.1.2+dfsg/debian/patches/romfile-compatibility.diff	2012-10-08 14:25:09.225656404 +0200
@@ -0,0 +1,39 @@ 
+Bug #24702: Fix PXE ROM size mismatch
+
+For pc-0.14 and older use the PXE ROMs from the deprecated etherboot-qemu
+package, which have different sizes. Without the patch the virtual PC gets
+build with the current ROM sizes. Loading then fails because the stored PCI ROM
+BAR size mismatches the configured size.
+--- a/hw/pc_piix.c
++++ b/hw/pc_piix.c
+@@ -433,6 +433,30 @@ static QEMUMachine pc_machine_v0_15 = {
+             .driver   = "virtio-balloon-pci",\
+             .property = "event_idx",\
+             .value    = "off",\
++        },{\
++            .driver   = "ne2000",\
++            .property = "romfile",\
++            .value   = "/usr/lib/etherboot/rtl8029.rom",\
++        },{\
++            .driver   = "rtl8139",\
++            .property = "romfile",\
++            .value   = "/usr/lib/etherboot/rtl8139.rom",\
++        },{\
++            .driver   = "e1000",\
++            .property = "romfile",\
++            .value   = "/usr/lib/etherboot/e1000-82540em.rom",\
++        },{\
++            .driver   = "pcnet",\
++            .property = "romfile",\
++            .value   = "/usr/lib/etherboot/pcnet32.rom",\
++        },{\
++            .driver   = "ne2k-isa",\
++            .property = "romfile",\
++            .value   = "/usr/lib/etherboot/ne.rom",\
++        },{\
++            .driver   = "virtio-net-pci",\
++            .property = "romfile",\
++            .value   = "/usr/lib/etherboot/virtio-net.rom",\
+         }
+ 
+ static QEMUMachine pc_machine_v0_14 = {
diff -urN qemu-kvm-1.1.2+dfsg.orig/debian/patches/series qemu-kvm-1.1.2+dfsg/debian/patches/series
--- qemu-kvm-1.1.2+dfsg.orig/debian/patches/series	2012-09-10 12:14:05.000000000 +0200
+++ qemu-kvm-1.1.2+dfsg/debian/patches/series	2012-10-08 14:24:51.497155189 +0200
@@ -8,3 +8,4 @@ 
 
 net-add--netdev-options-to-man-page.patch
 revert-serial-fix-retry-logic.patch
+romfile-compatibility.diff
diff -urN qemu-kvm-1.1.2+dfsg.orig/debian/control qemu-kvm-1.1.2+dfsg/debian/control
--- qemu-kvm-1.1.2+dfsg.orig/debian/control	2012-09-11 08:29:43.000000000 +0200
+++ qemu-kvm-1.1.2+dfsg/debian/control	2012-10-08 15:06:39.201155102 +0200
@@ -37,7 +37,8 @@ 
  seabios (>> 1.7.0~), vgabios (>= 0.6c-3~),
  qemu-keymaps, qemu-utils (>> 0.14.0),
  ipxe-qemu | ipxe (<< 1.0.0+git-20120202.f6840ba-2)
-Recommends: bridge-utils, iproute
+Recommends: bridge-utils, iproute,
+ etherboot-qemu
 Suggests: debootstrap, vde2, samba
 Provides: kvm
 Conflicts: kvm-source (<= 18-1), kvm-data (<= 66+dfsg-1.1), kvm (<< 1:0)