[PATCH v2 08/22] vfio: Enforce preserved devices are retrieved via LIVEUPDATE_SESSION_RETRIEVE_FD

[Pranjal Shrivastava]

On Thu, Jan 29, 2026 at 09:24:55PM +0000, David Matlack wrote:
> Enforce that files for incoming (preserved by previous kernel) VFIO
> devices are retrieved via LIVEUPDATE_SESSION_RETRIEVE_FD rather than by
> opening the corresponding VFIO character device or via
> VFIO_GROUP_GET_DEVICE_FD.
> 
> Both of these methods would result in VFIO initializing the device
> without access to the preserved state of the device passed by the
> previous kernel.
> 
> Signed-off-by: David Matlack <dmatlack at google.com>
> ---
>  drivers/vfio/device_cdev.c |  4 ++++
>  drivers/vfio/group.c       |  9 +++++++++
>  include/linux/vfio.h       | 18 ++++++++++++++++++
>  3 files changed, 31 insertions(+)
> 

Reviewed-by: Pranjal Shrivastava <praan at google.com>

Thanks,
Praan