[Intel-gfx] [PATCH 02/13] vfio: Introduce a vfio_uninit_group_dev() API call

[Jason Gunthorpe]

On Mon, Jul 19, 2021 at 02:11:38PM +0200, Cornelia Huck wrote:
> On Wed, Jul 14 2021, Jason Gunthorpe <jgg at nvidia.com> wrote:
> 
> > From: Max Gurtovoy <mgurtovoy at nvidia.com>
> >
> > This pairs with vfio_init_group_dev() and allows undoing any state that is
> > stored in the vfio_device unrelated to registration. Add appropriately
> > placed calls to all the drivers.
> >
> > The following patch will use this to add pre-registration state for the
> > device set.
> >
> > Signed-off-by: Max Gurtovoy <mgurtovoy at nvidia.com>
> > Signed-off-by: Jason Gunthorpe <jgg at nvidia.com>
> >  Documentation/driver-api/vfio.rst            |  4 ++-
> >  drivers/vfio/fsl-mc/vfio_fsl_mc.c            |  6 +++--
> >  drivers/vfio/mdev/vfio_mdev.c                | 13 +++++++---
> >  drivers/vfio/pci/vfio_pci.c                  |  6 +++--
> >  drivers/vfio/platform/vfio_platform_common.c |  7 +++--
> >  drivers/vfio/vfio.c                          |  5 ++++
> >  include/linux/vfio.h                         |  1 +
> >  samples/vfio-mdev/mbochs.c                   |  2 ++
> >  samples/vfio-mdev/mdpy.c                     | 25 ++++++++++--------
> >  samples/vfio-mdev/mtty.c                     | 27 ++++++++++++--------
> >  10 files changed, 64 insertions(+), 32 deletions(-)
> 
> (...)
> 
> > diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c
> > index e81b875b4d87b4..cf264d0bf11053 100644
> > +++ b/samples/vfio-mdev/mbochs.c
> > @@ -558,6 +558,7 @@ static int mbochs_probe(struct mdev_device *mdev)
> >  	return 0;
> >  
> >  err_mem:
> > +	vfio_uninit_group_dev(&mdev_state->vdev);
> >  	kfree(mdev_state->vconfig);
> >  	kfree(mdev_state);
> >  	return ret;

Doesn't this leak pages? Sigh.

> > @@ -571,6 +572,7 @@ static void mbochs_remove(struct mdev_device *mdev)
> >  	vfio_unregister_group_dev(&mdev_state->vdev);
> >  	kfree(mdev_state->pages);
> >  	kfree(mdev_state->vconfig);
> > +	vfio_uninit_group_dev(&mdev_state->vdev);
> 
> Does the location of the uninit vs the kfree matter? Even if not, it
> might be good to keep it consistent.

It does not, but I will reorder it anyhow

Jason