qemu-e2k/hw/nvram
Laszlo Ersek e6915b5f3a fw_cfg: unbreak migration compatibility for 2.4 and earlier machines
When I reviewed Marc's fw_cfg DMA patches, I completely missed that the
way we set dma_enabled would break migration.

Gerd explained the right way (see reference below): dma_enabled should be
set to true by default, and only true->false transitions should be
possible:

- when the user requests that with

    -global fw_cfg_mem.dma_enabled=off

  or

   -global fw_cfg_io.dma_enabled=off

  as appropriate for the platform,

- when HW_COMPAT_2_4 dictates it,

- when board code initializes fw_cfg without requesting DMA support.

Cc: Marc Marí <markmb@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Alexandre DERUMIER <aderumier@odiso.com>
Cc: qemu-stable@nongnu.org
Ref: http://thread.gmane.org/gmane.comp.emulators.qemu/390272/focus=391042
Ref: https://bugs.launchpad.net/qemu/+bug/1536487
Suggested-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Message-id: 1455823860-22268-1-git-send-email-lersek@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2016-02-26 10:06:40 +01:00
..
ds1225y.c hw: Clean up includes 2016-01-29 15:07:25 +00:00
eeprom93xx.c hw: Clean up includes 2016-01-29 15:07:25 +00:00
fw_cfg.c fw_cfg: unbreak migration compatibility for 2.4 and earlier machines 2016-02-26 10:06:40 +01:00
mac_nvram.c hw: fix some debug message format strings 2016-02-17 09:59:29 +11:00
Makefile.objs hw: move NVRAM interfaces to hw/nvram/, configure with default-configs/ 2013-04-08 18:13:16 +02:00
spapr_nvram.c ppc: Clean up includes 2016-01-29 15:07:22 +00:00