[Qemu-devel] [PATCH for-2.1 v2 0/2] Fix migration failure due to ACPI tables size changes

[Igor Mammedov <imammedo@redhat.com>]

Changes since v2:
  - addressed Laszlo's comments
     * fixing typos, rewording comments
     * dropping enum-ification of RAMBlock flags
     * adding zeroing out destination ramblock
     * replacing 'if' with assert() 
    
Changing the ACPI table size causes migration to break, and the memory
hotplug work opened our eyes on how horribly we were breaking things in
2.0 already.

To trigger issue start
  QEMU-1.7 with -M pc-i440fx-1.7 -device pci-bridge,chassis_nr=1
and try to migrate to QEMU-2.1 or QEMU-2.0 as result target will fail with:
  qemu-system-x86_64: Length mismatch: /rom@etc/acpi/tables: 2000 in != 3000

This fix allows target QEMU to load smaller RAMBlock into a bigger one
and fixes regression which was introduced since 2.0, allowing
forward migration from 1.7/2.0 to 2.1
Fix is also suitable for stable-2.0.


Igor Mammedov (2):
  migration: load smaller RAMBlock to a bigger one if permitted
  acpi: mark ACPI tables ROM blob as extend-able on migration

 arch_init.c             | 22 +++++++++++++++++-----
 exec.c                  |  8 ++++++++
 hw/core/loader.c        |  6 +++++-
 hw/i386/acpi-build.c    |  2 +-
 include/exec/memory.h   | 11 +++++++++++
 include/exec/ram_addr.h |  3 +++
 include/hw/loader.h     |  5 +++--
 memory.c                |  5 +++++
 8 files changed, 53 insertions(+), 9 deletions(-)

-- 
1.8.3.1