2020-03-29 14:59:21

by Chuhong Yuan

[permalink] [raw]
Subject: [PATCH v4] video: fbdev: vesafb: add missed release_region

The driver forgets to free the I/O region in remove and probe
failure.
Add the missed calls to fix it.

Since the success of request_region() is optional, add the "region" field
in vesafb_par to represent whether request_region() succeeds.
Then only call release_region() when "region" is not null.

Signed-off-by: Chuhong Yuan <[email protected]>
---
Changes in v4:
- Add a field in vesafb_par to represent whether request_region() succeeds.
- Only call release_region() when request_region() succeeds.
- Adjust the order in the error handler of probe.
- Modify commit message.

drivers/video/fbdev/vesafb.c | 16 +++++++++++-----
1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/drivers/video/fbdev/vesafb.c b/drivers/video/fbdev/vesafb.c
index a1fe24ea869b..df6de5a9dd4c 100644
--- a/drivers/video/fbdev/vesafb.c
+++ b/drivers/video/fbdev/vesafb.c
@@ -32,6 +32,7 @@
struct vesafb_par {
u32 pseudo_palette[256];
int wc_cookie;
+ struct resource *region;
};

static struct fb_var_screeninfo vesafb_defined = {
@@ -411,7 +412,7 @@ static int vesafb_probe(struct platform_device *dev)

/* request failure does not faze us, as vgacon probably has this
* region already (FIXME) */
- request_region(0x3c0, 32, "vesafb");
+ par->region = request_region(0x3c0, 32, "vesafb");

if (mtrr == 3) {
unsigned int temp_size = size_total;
@@ -439,7 +440,7 @@ static int vesafb_probe(struct platform_device *dev)
"vesafb: abort, cannot ioremap video memory 0x%x @ 0x%lx\n",
vesafb_fix.smem_len, vesafb_fix.smem_start);
err = -EIO;
- goto err;
+ goto err_release_region;
}

printk(KERN_INFO "vesafb: framebuffer at 0x%lx, mapped to 0x%p, "
@@ -458,19 +459,22 @@ static int vesafb_probe(struct platform_device *dev)

if (fb_alloc_cmap(&info->cmap, 256, 0) < 0) {
err = -ENOMEM;
- goto err;
+ goto err_release_region;
}
if (register_framebuffer(info)<0) {
err = -EINVAL;
fb_dealloc_cmap(&info->cmap);
- goto err;
+ goto err_release_region;
}
fb_info(info, "%s frame buffer device\n", info->fix.id);
return 0;
-err:
+err_release_region:
arch_phys_wc_del(par->wc_cookie);
if (info->screen_base)
iounmap(info->screen_base);
+ if (par->region)
+ release_region(0x3c0, 32);
+err:
framebuffer_release(info);
release_mem_region(vesafb_fix.smem_start, size_total);
return err;
@@ -481,6 +485,8 @@ static int vesafb_remove(struct platform_device *pdev)
struct fb_info *info = platform_get_drvdata(pdev);

unregister_framebuffer(info);
+ if (((struct vesafb_par *)(info->par))->region)
+ release_region(0x3c0, 32);
framebuffer_release(info);

return 0;
--
2.26.0


Subject: Re: [PATCH v4] video: fbdev: vesafb: add missed release_region


On 3/29/20 4:58 PM, Chuhong Yuan wrote:
> The driver forgets to free the I/O region in remove and probe
> failure.
> Add the missed calls to fix it.
>
> Since the success of request_region() is optional, add the "region" field
> in vesafb_par to represent whether request_region() succeeds.
> Then only call release_region() when "region" is not null.
>
> Signed-off-by: Chuhong Yuan <[email protected]>

Patch queued for v5.8, thanks.

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

> ---
> Changes in v4:
> - Add a field in vesafb_par to represent whether request_region() succeeds.
> - Only call release_region() when request_region() succeeds.
> - Adjust the order in the error handler of probe.
> - Modify commit message.
>
> drivers/video/fbdev/vesafb.c | 16 +++++++++++-----
> 1 file changed, 11 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/video/fbdev/vesafb.c b/drivers/video/fbdev/vesafb.c
> index a1fe24ea869b..df6de5a9dd4c 100644
> --- a/drivers/video/fbdev/vesafb.c
> +++ b/drivers/video/fbdev/vesafb.c
> @@ -32,6 +32,7 @@
> struct vesafb_par {
> u32 pseudo_palette[256];
> int wc_cookie;
> + struct resource *region;
> };
>
> static struct fb_var_screeninfo vesafb_defined = {
> @@ -411,7 +412,7 @@ static int vesafb_probe(struct platform_device *dev)
>
> /* request failure does not faze us, as vgacon probably has this
> * region already (FIXME) */
> - request_region(0x3c0, 32, "vesafb");
> + par->region = request_region(0x3c0, 32, "vesafb");
>
> if (mtrr == 3) {
> unsigned int temp_size = size_total;
> @@ -439,7 +440,7 @@ static int vesafb_probe(struct platform_device *dev)
> "vesafb: abort, cannot ioremap video memory 0x%x @ 0x%lx\n",
> vesafb_fix.smem_len, vesafb_fix.smem_start);
> err = -EIO;
> - goto err;
> + goto err_release_region;
> }
>
> printk(KERN_INFO "vesafb: framebuffer at 0x%lx, mapped to 0x%p, "
> @@ -458,19 +459,22 @@ static int vesafb_probe(struct platform_device *dev)
>
> if (fb_alloc_cmap(&info->cmap, 256, 0) < 0) {
> err = -ENOMEM;
> - goto err;
> + goto err_release_region;
> }
> if (register_framebuffer(info)<0) {
> err = -EINVAL;
> fb_dealloc_cmap(&info->cmap);
> - goto err;
> + goto err_release_region;
> }
> fb_info(info, "%s frame buffer device\n", info->fix.id);
> return 0;
> -err:
> +err_release_region:
> arch_phys_wc_del(par->wc_cookie);
> if (info->screen_base)
> iounmap(info->screen_base);
> + if (par->region)
> + release_region(0x3c0, 32);
> +err:
> framebuffer_release(info);
> release_mem_region(vesafb_fix.smem_start, size_total);
> return err;
> @@ -481,6 +485,8 @@ static int vesafb_remove(struct platform_device *pdev)
> struct fb_info *info = platform_get_drvdata(pdev);
>
> unregister_framebuffer(info);
> + if (((struct vesafb_par *)(info->par))->region)
> + release_region(0x3c0, 32);
> framebuffer_release(info);
>
> return 0;
>