From: Jacob Pan Date: Wed, 18 Jun 2025 23:46:17 +0000 (-0700) Subject: vfio: Fix unbalanced vfio_df_close call in no-iommu mode X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b25e271b377999191b12f0afbe1861edcf57e3fe;p=thirdparty%2Flinux.git vfio: Fix unbalanced vfio_df_close call in no-iommu mode For devices with no-iommu enabled in IOMMUFD VFIO compat mode, the group open path skips vfio_df_open(), leaving open_count at 0. This causes a warning in vfio_assert_device_open(device) when vfio_df_close() is called during group close. The correct behavior is to skip only the IOMMUFD bind in the device open path for no-iommu devices. Commit 6086efe73498 omitted vfio_df_open(), which was too broad. This patch restores the previous behavior, ensuring the vfio_df_open is called in the group open path. Fixes: 6086efe73498 ("vfio-iommufd: Move noiommu compat validation out of vfio_iommufd_bind()") Suggested-by: Alex Williamson Suggested-by: Jason Gunthorpe Signed-off-by: Jacob Pan Reviewed-by: Jason Gunthorpe Link: https://lore.kernel.org/r/20250618234618.1910456-1-jacob.pan@linux.microsoft.com Signed-off-by: Alex Williamson --- diff --git a/drivers/vfio/group.c b/drivers/vfio/group.c index c321d442f0da0..c376a6279de0e 100644 --- a/drivers/vfio/group.c +++ b/drivers/vfio/group.c @@ -192,11 +192,10 @@ static int vfio_df_group_open(struct vfio_device_file *df) * implies they expected translation to exist */ if (!capable(CAP_SYS_RAWIO) || - vfio_iommufd_device_has_compat_ioas(device, df->iommufd)) + vfio_iommufd_device_has_compat_ioas(device, df->iommufd)) { ret = -EPERM; - else - ret = 0; - goto out_put_kvm; + goto out_put_kvm; + } } ret = vfio_df_open(df); diff --git a/drivers/vfio/iommufd.c b/drivers/vfio/iommufd.c index c8c3a2d53f86e..a38d262c60280 100644 --- a/drivers/vfio/iommufd.c +++ b/drivers/vfio/iommufd.c @@ -25,6 +25,10 @@ int vfio_df_iommufd_bind(struct vfio_device_file *df) lockdep_assert_held(&vdev->dev_set->lock); + /* Returns 0 to permit device opening under noiommu mode */ + if (vfio_device_is_noiommu(vdev)) + return 0; + return vdev->ops->bind_iommufd(vdev, ictx, &df->devid); }