[PATCH v4 0/3] vfio/pci: Check the device set open_count on reset

[Anthony DeRossi <ajderossi@gmail.com>]

I took Alex's suggestion on the v2 patch to add an open count to the device
set. This simplified the final patch and might generally be useful for other
drivers.

The first patch in the series fixes a life cycle issue that was discovered
while adding open_count to vfio_device_set. It is also fixed by a patch [1] in
Jason's "Connect VFIO to IOMMU" series.

The third patch is a rework of the original fix that uses the new device set
open_count instead of the private open_count in vfio_device.

[1] https://lore.kernel.org/kvm/1-v1-4991695894d8+211-vfio_iommufd_jgg@nvidia.com/

Anthony

v3 -> v4:
- Added a patch to fix device registration life cycle
- Added a patch to add a public open_count on vfio_device_set
- Changed the implementation to avoid private open_count usage
v3: https://lore.kernel.org/kvm/20221102055732.2110-1-ajderossi@gmail.com/

v2 -> v3:
- Added WARN_ON()
- Revised commit message
v2: https://lore.kernel.org/kvm/20221026194245.1769-1-ajderossi@gmail.com/

v1 -> v2:
- Changed reset behavior instead of open_count ordering
- Retitled from "vfio: Decrement open_count before close_device()"
v1: https://lore.kernel.org/kvm/20221025193820.4412-1-ajderossi@gmail.com/

Anthony DeRossi (3):
  vfio: Fix container device registration life cycle
  vfio: Add an open counter to vfio_device_set
  vfio/pci: Check the device set open_count on reset

 drivers/vfio/pci/vfio_pci_core.c | 10 +++++-----
 drivers/vfio/vfio_main.c         | 16 +++++++++++-----
 include/linux/vfio.h             |  1 +
 3 files changed, 17 insertions(+), 10 deletions(-)

-- 
2.37.4