Peter Maydell <address@hidden> writes:
On 5 April 2013 17:47, Anthony Liguori <address@hidden> wrote:
Kevin Wolf <address@hidden> writes:
From: KONRAD Frederic <address@hidden>
The virtio-blk-x configuration is not in sync with virtio-blk configuration.
So this patch remove the virtio-blk-x configuration field, and use virtio-blk
one for setting the properties.
This also remove a useless configuration copy in virtio_blk_device_init.
Signed-off-by: KONRAD Frederic <address@hidden>
Tested-by: Cornelia Huck <address@hidden>
Signed-off-by: Kevin Wolf <address@hidden>
This breaks -M pc-1.0 as it breaks global properties.
The first level analysis of why this happens:
(1) global values are set as part of DeviceState's instance_init function
[and we set the config_wce field to 0 here]
(2) virtio_blk_pci_instance_init is a subclass instance_init so runs second
(3) it calls object_initialize on its embedded virtio-blk object
(4) the DeviceState instance_init for that child object sets the
properties to their init values [thus resetting config_wce to 1]
The effect is that at the moment you can't have a property on
a parent object whose value is stored in the child object
(unless you do something hacky like read the default before
calling object_initialize and restore it afterwards].
It seems to me that the underlying problem here is that we
set global values too early -- they should be set after a
device is completely instance_init'd, not halfway through init.
Here is an in-progress series that forwards properties from the
virtio-blk-pci to virtio-blk.
I think it's the best solution. The approach needs some polishing but I
wanted to share early.
https://github.com/aliguori/qemu/commits/qom-forward.1
Regards,
Anthony Liguori
-- PMM