| Message ID | 1550015279-42723-1-git-send-email-wen.yang99@zte.com.cn (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | None | expand |
Hi On 2019-02-13 00:47, Wen Yang wrote: > The call to of_parse_phandle() returns a node pointer with refcount > incremented thus it must be explicitly decremented here after the last > usage. > The of_find_device_by_node() takes a reference to the underlying device > structure, we also should release that reference. > This patch fixes those two issues. > > Hans Verkuil says: > The cec driver should never take a reference of the hdmi device. > It never accesses the HDMI device, it only needs the HDMI device pointer as > a key in the notifier list. > The real problem is that several CEC drivers take a reference of the HDMI > device and never release it. So those drivers need to be fixed. > > Fixes: a93d429b51fb ("[media] s5p-cec: add cec-notifier support, move out of staging") > Suggested-by: Hans Verkuil (hansverk) <hansverk@cisco.com> > Signed-off-by: Wen Yang <wen.yang99@zte.com.cn> > Cc: Hans Verkuil (hansverk) <hansverk@cisco.com> > Cc: Hans Verkuil <hans.verkuil@cisco.com> > Cc: Marek Szyprowski <m.szyprowski@samsung.com> > Cc: Mauro Carvalho Chehab <mchehab@kernel.org> > Cc: Wen Yang <yellowriver2010@hotmail.com> > Cc: linux-samsung-soc@vger.kernel.org > Cc: linux-media@vger.kernel.org Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> > --- > v2->v1: > - move of_node_put() to just after the 'hdmi_dev = of_find_device_by_node(np)'. > - put_device() can be done before the cec = devm_kzalloc line. > > drivers/media/platform/s5p-cec/s5p_cec.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/media/platform/s5p-cec/s5p_cec.c b/drivers/media/platform/s5p-cec/s5p_cec.c > index 8837e26..1f5c355 100644 > --- a/drivers/media/platform/s5p-cec/s5p_cec.c > +++ b/drivers/media/platform/s5p-cec/s5p_cec.c > @@ -192,9 +192,11 @@ static int s5p_cec_probe(struct platform_device *pdev) > return -ENODEV; > } > hdmi_dev = of_find_device_by_node(np); > + of_node_put(np); > if (hdmi_dev == NULL) > return -EPROBE_DEFER; > > + put_device(&hdmi_dev->dev); > cec = devm_kzalloc(&pdev->dev, sizeof(*cec), GFP_KERNEL); > if (!cec) > return -ENOMEM; Best regards
diff --git a/drivers/media/platform/s5p-cec/s5p_cec.c b/drivers/media/platform/s5p-cec/s5p_cec.c index 8837e26..1f5c355 100644 --- a/drivers/media/platform/s5p-cec/s5p_cec.c +++ b/drivers/media/platform/s5p-cec/s5p_cec.c @@ -192,9 +192,11 @@ static int s5p_cec_probe(struct platform_device *pdev) return -ENODEV; } hdmi_dev = of_find_device_by_node(np); + of_node_put(np); if (hdmi_dev == NULL) return -EPROBE_DEFER; + put_device(&hdmi_dev->dev); cec = devm_kzalloc(&pdev->dev, sizeof(*cec), GFP_KERNEL); if (!cec) return -ENOMEM;
The call to of_parse_phandle() returns a node pointer with refcount incremented thus it must be explicitly decremented here after the last usage. The of_find_device_by_node() takes a reference to the underlying device structure, we also should release that reference. This patch fixes those two issues. Hans Verkuil says: The cec driver should never take a reference of the hdmi device. It never accesses the HDMI device, it only needs the HDMI device pointer as a key in the notifier list. The real problem is that several CEC drivers take a reference of the HDMI device and never release it. So those drivers need to be fixed. Fixes: a93d429b51fb ("[media] s5p-cec: add cec-notifier support, move out of staging") Suggested-by: Hans Verkuil (hansverk) <hansverk@cisco.com> Signed-off-by: Wen Yang <wen.yang99@zte.com.cn> Cc: Hans Verkuil (hansverk) <hansverk@cisco.com> Cc: Hans Verkuil <hans.verkuil@cisco.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Wen Yang <yellowriver2010@hotmail.com> Cc: linux-samsung-soc@vger.kernel.org Cc: linux-media@vger.kernel.org --- v2->v1: - move of_node_put() to just after the 'hdmi_dev = of_find_device_by_node(np)'. - put_device() can be done before the cec = devm_kzalloc line. drivers/media/platform/s5p-cec/s5p_cec.c | 2 ++ 1 file changed, 2 insertions(+)