On Wed, May 20, 2020 at 9:54 PM Hans de Goede <hdegoede@xxxxxxxxxx> wrote:
>
> Until this commit the mainline kernel version (this version) of the
> vboxguest module contained a bug where it defined
> VBGL_IOCTL_VMMDEV_REQUEST_BIG and VBGL_IOCTL_LOG using
> _IOC(_IOC_READ | _IOC_WRITE, 'V', ...) instead of
> _IO(V, ...) as the out of tree VirtualBox upstream version does.
>
> Since the VirtualBox userspace bits are always built against VirtualBox
> upstream's headers, this means that so far the mainline kernel version
> of the vboxguest module has been failing these 2 ioctls with -ENOTTY.
> I guess that VBGL_IOCTL_VMMDEV_REQUEST_BIG is never used causing us to
> not hit that one and sofar the vboxguest driver has failed to actually
> log any log messages passed it through VBGL_IOCTL_LOG.
>
> This commit changes the VBGL_IOCTL_VMMDEV_REQUEST_BIG and VBGL_IOCTL_LOG
> defines to match the out of tree VirtualBox upstream vboxguest version,
> while keeping compatibility with the old wrong request defines so as
> to not break the kernel ABI in case someone has been using the old
> request defines.
>
> Fixes: f6ddd094f579 ("virt: Add vboxguest driver for Virtual Box Guest integration UAPI")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Indeed, this sounds like the best fix
Reviewed-by: Arnd Bergmann <arnd@xxxxxxxx>
