diff options
| author | Hans de Goede <hdegoede@redhat.com> | 2022-10-23 21:22:14 +0100 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@kernel.org> | 2022-11-25 08:19:24 +0000 |
| commit | da0dd507fa279c33813ae6f28e47c61ce065586c (patch) | |
| tree | 461e3fb646dbeaaf2826c27bbb1260c19f53a7cd /drivers/staging | |
| parent | ac8dd062aa6cb095096e02240f497786891317b0 (diff) | |
media: atomisp: Fix deadlock when the /dev/video# node is closed while still streaming
atomisp_release() was taking pipe->vb_queue_mutex + isp->mutex at the
same time. But if the /dev/video# node is closed while still streaming
then vb2_queue_release() will call atomisp_stop_streaming() which takes
isp->mutex itself, leading to a deadlock.
To fix this only take isp->mutex after cleaning up the v4l2_fh /
the vb2_queue. While at it switch to vb2_fop_release() which will take
pipe->vb_queue_mutex for us, which also resolves a FIXME comment.
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Diffstat (limited to 'drivers/staging')
| -rw-r--r-- | drivers/staging/media/atomisp/pci/atomisp_fops.c | 21 |
1 files changed, 5 insertions, 16 deletions
diff --git a/drivers/staging/media/atomisp/pci/atomisp_fops.c b/drivers/staging/media/atomisp/pci/atomisp_fops.c index 101663a07112..b627c3110ca7 100644 --- a/drivers/staging/media/atomisp/pci/atomisp_fops.c +++ b/drivers/staging/media/atomisp/pci/atomisp_fops.c @@ -860,23 +860,14 @@ static int atomisp_release(struct file *file) v4l2_fh_init(&fh.vfh, vdev); - mutex_lock(&pipe->vb_queue_mutex); - mutex_lock(&isp->mutex); - dev_dbg(isp->dev, "release device %s\n", vdev->name); asd->subdev.devnode = vdev; - /* - * FIXME This if is copied from _vb2_fop_release, this cannot use that - * because that calls v4l2_fh_release() earlier then this function. - * Maybe we can release the fh earlier though, it does not look like - * anything needs it after this. - */ - if (file->private_data == vdev->queue->owner) { - vb2_queue_release(vdev->queue); - vdev->queue->owner = NULL; - } + /* Note file must not be used after this! */ + vb2_fop_release(file); + + mutex_lock(&isp->mutex); pipe->users--; if (pipe->users) @@ -939,9 +930,7 @@ done: V4L2_SEL_TGT_COMPOSE, 0, &clear_compose); mutex_unlock(&isp->mutex); - mutex_unlock(&pipe->vb_queue_mutex); - - return v4l2_fh_release(file); + return 0; } const struct v4l2_file_operations atomisp_fops = { |