2019-11-16 15:49:01

by Chuhong Yuan

[permalink] [raw]
Subject: [PATCH] video: fbdev: arcfb: add missed free_irq

The driver forgets to free irq in remove which is requested in
probe.
Add the missed call to fix it.

Signed-off-by: Chuhong Yuan <[email protected]>
---
drivers/video/fbdev/arcfb.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/video/fbdev/arcfb.c b/drivers/video/fbdev/arcfb.c
index a48741aab240..7aed01f001a4 100644
--- a/drivers/video/fbdev/arcfb.c
+++ b/drivers/video/fbdev/arcfb.c
@@ -590,8 +590,11 @@ static int arcfb_probe(struct platform_device *dev)
static int arcfb_remove(struct platform_device *dev)
{
struct fb_info *info = platform_get_drvdata(dev);
+ struct arcfb_par *par = info->par;

if (info) {
+ if (irq)
+ free_irq(par->irq, info);
unregister_framebuffer(info);
vfree((void __force *)info->screen_base);
framebuffer_release(info);
--
2.24.0


Subject: Re: [PATCH] video: fbdev: arcfb: add missed free_irq


On 11/16/19 4:44 PM, Chuhong Yuan wrote:
> The driver forgets to free irq in remove which is requested in
> probe.
> Add the missed call to fix it.
>
> Signed-off-by: Chuhong Yuan <[email protected]>
> ---
> drivers/video/fbdev/arcfb.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/video/fbdev/arcfb.c b/drivers/video/fbdev/arcfb.c
> index a48741aab240..7aed01f001a4 100644
> --- a/drivers/video/fbdev/arcfb.c
> +++ b/drivers/video/fbdev/arcfb.c
> @@ -590,8 +590,11 @@ static int arcfb_probe(struct platform_device *dev)
> static int arcfb_remove(struct platform_device *dev)
> {
> struct fb_info *info = platform_get_drvdata(dev);
> + struct arcfb_par *par = info->par;
>
> if (info) {
> + if (irq)
> + free_irq(par->irq, info);
> unregister_framebuffer(info);

We cannot free IRQ while framebuffer is registered (as we can
deadlock in arcfb_ioctl()).

Also it seems that ordering in the probe function is wrong
(it should not request IRQ or initialize the hardware after
registering framebuffer).

> vfree((void __force *)info->screen_base);
> framebuffer_release(info);

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics