| Message ID | 20200613232357.18155-1-wu000273@umn.edu (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | media: vsp1: Fix a reference count leak. | expand |
Hi Qiushi, (CC'ing Rafael and Geert) Thank you for the patch. On Sat, Jun 13, 2020 at 06:23:57PM -0500, wu000273@umn.edu wrote: > From: Qiushi Wu <wu000273@umn.edu> > > pm_runtime_get_sync() increments the runtime PM usage counter even > when it returns an error code, causing incorrect ref count if > pm_runtime_put_noidle() is not called in error handling paths. > Thus call pm_runtime_put_noidle() if pm_runtime_get_sync() fails. > > Fixes: 1e6af546ee66 ("[media] v4l: vsp1: Implement runtime PM support") > Signed-off-by: Qiushi Wu <wu000273@umn.edu> https://lore.kernel.org/dri-devel/20200614134655.GA5960@pendragon.ideasonboard.com/ I really wonder if mass-patching all drivers is the best way forward. > --- > drivers/media/platform/vsp1/vsp1_drv.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/media/platform/vsp1/vsp1_drv.c b/drivers/media/platform/vsp1/vsp1_drv.c > index c650e45bb0ad..222c9e1261a0 100644 > --- a/drivers/media/platform/vsp1/vsp1_drv.c > +++ b/drivers/media/platform/vsp1/vsp1_drv.c > @@ -846,8 +846,10 @@ static int vsp1_probe(struct platform_device *pdev) > pm_runtime_enable(&pdev->dev); > > ret = pm_runtime_get_sync(&pdev->dev); > - if (ret < 0) > + if (ret < 0) { > + pm_runtime_put_noidle(&pdev->dev); > goto done; > + } > > vsp1->version = vsp1_read(vsp1, VI6_IP_VERSION); > pm_runtime_put_sync(&pdev->dev);
On Tue, Jun 16, 2020 at 05:07:34AM +0300, Laurent Pinchart wrote: > Hi Qiushi, > > (CC'ing Rafael and Geert) > > Thank you for the patch. > > On Sat, Jun 13, 2020 at 06:23:57PM -0500, wu000273@umn.edu wrote: > > From: Qiushi Wu <wu000273@umn.edu> > > > > pm_runtime_get_sync() increments the runtime PM usage counter even > > when it returns an error code, causing incorrect ref count if > > pm_runtime_put_noidle() is not called in error handling paths. > > Thus call pm_runtime_put_noidle() if pm_runtime_get_sync() fails. > > > > Fixes: 1e6af546ee66 ("[media] v4l: vsp1: Implement runtime PM support") > > Signed-off-by: Qiushi Wu <wu000273@umn.edu> > > https://lore.kernel.org/dri-devel/20200614134655.GA5960@pendragon.ideasonboard.com/ > > I really wonder if mass-patching all drivers is the best way forward. Also, https://lore.kernel.org/linux-media/20200608052919.4984-1-dinghao.liu@zju.edu.cn/ > > --- > > drivers/media/platform/vsp1/vsp1_drv.c | 4 +++- > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/media/platform/vsp1/vsp1_drv.c b/drivers/media/platform/vsp1/vsp1_drv.c > > index c650e45bb0ad..222c9e1261a0 100644 > > --- a/drivers/media/platform/vsp1/vsp1_drv.c > > +++ b/drivers/media/platform/vsp1/vsp1_drv.c > > @@ -846,8 +846,10 @@ static int vsp1_probe(struct platform_device *pdev) > > pm_runtime_enable(&pdev->dev); > > > > ret = pm_runtime_get_sync(&pdev->dev); > > - if (ret < 0) > > + if (ret < 0) { > > + pm_runtime_put_noidle(&pdev->dev); > > goto done; > > + } > > > > vsp1->version = vsp1_read(vsp1, VI6_IP_VERSION); > > pm_runtime_put_sync(&pdev->dev);
On 16/06/2020 04:09, Laurent Pinchart wrote: > On Tue, Jun 16, 2020 at 05:07:34AM +0300, Laurent Pinchart wrote: >> Hi Qiushi, >> >> (CC'ing Rafael and Geert) >> >> Thank you for the patch. >> >> On Sat, Jun 13, 2020 at 06:23:57PM -0500, wu000273@umn.edu wrote: >>> From: Qiushi Wu <wu000273@umn.edu> >>> >>> pm_runtime_get_sync() increments the runtime PM usage counter even >>> when it returns an error code, causing incorrect ref count if >>> pm_runtime_put_noidle() is not called in error handling paths. >>> Thus call pm_runtime_put_noidle() if pm_runtime_get_sync() fails. >>> >>> Fixes: 1e6af546ee66 ("[media] v4l: vsp1: Implement runtime PM support") >>> Signed-off-by: Qiushi Wu <wu000273@umn.edu> >> >> https://lore.kernel.org/dri-devel/20200614134655.GA5960@pendragon.ideasonboard.com/ >> >> I really wonder if mass-patching all drivers is the best way forward. > > Also, > > https://lore.kernel.org/linux-media/20200608052919.4984-1-dinghao.liu@zju.edu.cn/ I also stop applying these patches. In part because of what Laurent says (I'd like to have some consensus on this as well), and in part because there are at least three different devs working on this (Qiushi Wu <wu000273@umn.edu>, Aditya Pakki <pakki001@umn.edu> and Dinghao Liu <dinghao.liu@zju.edu.cn>) and I am getting duplicate patches. So I stop applying these pm_runtime_get_sync() patches until it is clear that this is the way forward. Other ref count issues I will still apply, but it would be great if Qiushi Wu, Aditya Pakki and Dinghao Liu can work together to avoid duplicate patches. Regards, Hans > >>> --- >>> drivers/media/platform/vsp1/vsp1_drv.c | 4 +++- >>> 1 file changed, 3 insertions(+), 1 deletion(-) >>> >>> diff --git a/drivers/media/platform/vsp1/vsp1_drv.c b/drivers/media/platform/vsp1/vsp1_drv.c >>> index c650e45bb0ad..222c9e1261a0 100644 >>> --- a/drivers/media/platform/vsp1/vsp1_drv.c >>> +++ b/drivers/media/platform/vsp1/vsp1_drv.c >>> @@ -846,8 +846,10 @@ static int vsp1_probe(struct platform_device *pdev) >>> pm_runtime_enable(&pdev->dev); >>> >>> ret = pm_runtime_get_sync(&pdev->dev); >>> - if (ret < 0) >>> + if (ret < 0) { >>> + pm_runtime_put_noidle(&pdev->dev); >>> goto done; >>> + } >>> >>> vsp1->version = vsp1_read(vsp1, VI6_IP_VERSION); >>> pm_runtime_put_sync(&pdev->dev); >
diff --git a/drivers/media/platform/vsp1/vsp1_drv.c b/drivers/media/platform/vsp1/vsp1_drv.c index c650e45bb0ad..222c9e1261a0 100644 --- a/drivers/media/platform/vsp1/vsp1_drv.c +++ b/drivers/media/platform/vsp1/vsp1_drv.c @@ -846,8 +846,10 @@ static int vsp1_probe(struct platform_device *pdev) pm_runtime_enable(&pdev->dev); ret = pm_runtime_get_sync(&pdev->dev); - if (ret < 0) + if (ret < 0) { + pm_runtime_put_noidle(&pdev->dev); goto done; + } vsp1->version = vsp1_read(vsp1, VI6_IP_VERSION); pm_runtime_put_sync(&pdev->dev);