A later patch will require this locking - currently under the ioas mutex the hwpt can not have a 0 reference and be on the list. Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx> Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx> --- drivers/iommu/iommufd/device.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c index dcfaf6567420e0..0a80ff7b2e0d79 100644 --- a/drivers/iommu/iommufd/device.c +++ b/drivers/iommu/iommufd/device.c @@ -282,7 +282,10 @@ static int iommufd_device_auto_get_domain(struct iommufd_device *idev, if (!hwpt->auto_domain) continue; + if (!iommufd_lock_obj(&hwpt->obj)) + continue; rc = iommufd_device_do_attach(idev, hwpt); + iommufd_put_object(&hwpt->obj); /* * -EINVAL means the domain is incompatible with the device. -- 2.39.2
