Unhelpful feedback "DrvVD: Configuration error: keys incorrect at level 0"

[krichter]

Starting a VM which formerly worked fine fails due to

    DrvVD: Configuration error: keys incorrect at level 0 (VERR_PDM_DRVINS_UNKNOWN_CFG_VALUES).
    AHCI: Failed to attach drive to Port0 (VERR_PDM_DRVINS_UNKNOWN_CFG_VALUES).


    Fehlercode:
    NS_ERROR_FAILURE (0x80004005)
    Komponente:
    ConsoleWrap
    Interface:
    IConsole {872da645-4a9b-1727-bee2-5585105b9eed}

displayed in dialog after start. It'd be helpful to know what failure occurred for what reason and what are useful steps to proceed. It looks like an error in the configuration file, but it's just too useless to guess if you could improve the feedback.

experienced on Ubuntu 16.10 host with Gentoo guest

[krichter]

This is caused by an errornous directive

    <ExtraDataItem name="VBoxInternal/Devices/ahci/0/LUN#0/Config/IgnoreFlsh" value="0"/>

which should be

    <ExtraDataItem name="VBoxInternal/Devices/ahci/0/LUN#0/Config/IgnoreFlush" value="0"/>

so it'd be useful to tell the user that instead of providing internal information which only VirtualBox devs can understand.

Is it wise/necessary that VBoxManage setextradata doesn't fail when setting these errornous values.

[Frank Mehnert]

The user is not supposed to modify such internal configuration manually. If you do you should know what you are doing. The same would happen if you change a random key in the Windows registry. It might work but not necessarily. And I don't think the error message is that bad: VERR_PDM_DRVINS_UNKNOWN_CFG_VALUES points to some problem with the configuration. I guess it would be even better if the message contains the full help text for this error:

"A driver encountered an unknown configuration value. This means that the driver is potentially misconfigured and the driver. construction failed because of this."