All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH] drm/mgag200: Fail on I2C initialization errors
@ 2022-05-05 15:22 Thomas Zimmermann
  2022-05-05 15:49 ` Jocelyn Falempe
  2022-05-05 21:06   ` kernel test robot
  0 siblings, 2 replies; 8+ messages in thread
From: Thomas Zimmermann @ 2022-05-05 15:22 UTC (permalink / raw)
  To: airlied, jfalempe, daniel; +Cc: Thomas Zimmermann, dri-devel

Initialization of the I2C adapter was allowed to fail. The mgag200
driver would have continued without DDC support. Had this happened in
practice, it would have led to segmentation faults in the connector
code. Resolve this problem by failing driver initialization on I2C-
related errors.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/gpu/drm/mgag200/mgag200_i2c.c  | 13 ++++++++-----
 drivers/gpu/drm/mgag200/mgag200_mode.c |  6 ++++--
 2 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/mgag200/mgag200_i2c.c b/drivers/gpu/drm/mgag200/mgag200_i2c.c
index ac8e34eef5138..31e2c641a7814 100644
--- a/drivers/gpu/drm/mgag200/mgag200_i2c.c
+++ b/drivers/gpu/drm/mgag200/mgag200_i2c.c
@@ -120,7 +120,7 @@ struct mga_i2c_chan *mgag200_i2c_create(struct drm_device *dev)
 
 	i2c = kzalloc(sizeof(struct mga_i2c_chan), GFP_KERNEL);
 	if (!i2c)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 	i2c->data = data;
 	i2c->clock = clock;
@@ -142,11 +142,14 @@ struct mga_i2c_chan *mgag200_i2c_create(struct drm_device *dev)
 	i2c->bit.getscl		= mga_gpio_getscl;
 
 	ret = i2c_bit_add_bus(&i2c->adapter);
-	if (ret) {
-		kfree(i2c);
-		i2c = NULL;
-	}
+	if (ret)
+		goto err_kfree;
+
 	return i2c;
+
+err_kfree:
+	kfree(i2c);
+	return ERR_PTR(ret);
 }
 
 void mgag200_i2c_destroy(struct mga_i2c_chan *i2c)
diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c b/drivers/gpu/drm/mgag200/mgag200_mode.c
index abde7655477db..79557ca056f08 100644
--- a/drivers/gpu/drm/mgag200/mgag200_mode.c
+++ b/drivers/gpu/drm/mgag200/mgag200_mode.c
@@ -815,8 +815,10 @@ static int mgag200_vga_connector_init(struct mga_device *mdev)
 	int ret;
 
 	i2c = mgag200_i2c_create(dev);
-	if (!i2c)
-		drm_warn(dev, "failed to add DDC bus\n");
+	if (IS_ERR(i2c)) {
+		drm_err(dev, "failed to add DDC bus: %d\n", ret);
+		return PTR_ERR(i2c);
+	}
 
 	ret = drm_connector_init_with_ddc(dev, connector,
 					  &mga_vga_connector_funcs,
-- 
2.36.0


^ permalink raw reply related	[flat|nested] 8+ messages in thread
* Re: [PATCH] drm/mgag200: Fail on I2C initialization errors
  2022-05-05 15:22 [PATCH] drm/mgag200: Fail on I2C initialization errors Thomas Zimmermann
@ 2022-05-05 15:49 ` Jocelyn Falempe
  2022-05-06 10:53   ` Thomas Zimmermann
  2022-05-05 21:06   ` kernel test robot
  1 sibling, 1 reply; 8+ messages in thread
From: Jocelyn Falempe @ 2022-05-05 15:49 UTC (permalink / raw)
  To: Thomas Zimmermann, airlied, daniel; +Cc: dri-devel

On 05/05/2022 17:22, Thomas Zimmermann wrote:
> Initialization of the I2C adapter was allowed to fail. The mgag200
> driver would have continued without DDC support. Had this happened in
> practice, it would have led to segmentation faults in the connector
> code. Resolve this problem by failing driver initialization on I2C-
> related errors.

Reviewed-by: Jocelyn Falempe <jfalempe@redhat.com>

> 
> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
> ---
>   drivers/gpu/drm/mgag200/mgag200_i2c.c  | 13 ++++++++-----
>   drivers/gpu/drm/mgag200/mgag200_mode.c |  6 ++++--
>   2 files changed, 12 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/gpu/drm/mgag200/mgag200_i2c.c b/drivers/gpu/drm/mgag200/mgag200_i2c.c
> index ac8e34eef5138..31e2c641a7814 100644
> --- a/drivers/gpu/drm/mgag200/mgag200_i2c.c
> +++ b/drivers/gpu/drm/mgag200/mgag200_i2c.c
> @@ -120,7 +120,7 @@ struct mga_i2c_chan *mgag200_i2c_create(struct drm_device *dev)
>   
>   	i2c = kzalloc(sizeof(struct mga_i2c_chan), GFP_KERNEL);
>   	if (!i2c)
> -		return NULL;
> +		return ERR_PTR(-ENOMEM);
>   
>   	i2c->data = data;
>   	i2c->clock = clock;
> @@ -142,11 +142,14 @@ struct mga_i2c_chan *mgag200_i2c_create(struct drm_device *dev)
>   	i2c->bit.getscl		= mga_gpio_getscl;
>   
>   	ret = i2c_bit_add_bus(&i2c->adapter);
> -	if (ret) {
> -		kfree(i2c);
> -		i2c = NULL;
> -	}
> +	if (ret)
> +		goto err_kfree;
> +
>   	return i2c;
> +
> +err_kfree:
> +	kfree(i2c);
> +	return ERR_PTR(ret);
>   }
>   
>   void mgag200_i2c_destroy(struct mga_i2c_chan *i2c)
> diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c b/drivers/gpu/drm/mgag200/mgag200_mode.c
> index abde7655477db..79557ca056f08 100644
> --- a/drivers/gpu/drm/mgag200/mgag200_mode.c
> +++ b/drivers/gpu/drm/mgag200/mgag200_mode.c
> @@ -815,8 +815,10 @@ static int mgag200_vga_connector_init(struct mga_device *mdev)
>   	int ret;
>   
>   	i2c = mgag200_i2c_create(dev);
> -	if (!i2c)
> -		drm_warn(dev, "failed to add DDC bus\n");
> +	if (IS_ERR(i2c)) {
> +		drm_err(dev, "failed to add DDC bus: %d\n", ret);
> +		return PTR_ERR(i2c);
> +	}
>   
>   	ret = drm_connector_init_with_ddc(dev, connector,
>   					  &mga_vga_connector_funcs,


^ permalink raw reply	[flat|nested] 8+ messages in thread
* Re: [PATCH] drm/mgag200: Fail on I2C initialization errors
  2022-05-05 15:22 [PATCH] drm/mgag200: Fail on I2C initialization errors Thomas Zimmermann
@ 2022-05-05 21:06   ` kernel test robot
  2022-05-05 21:06   ` kernel test robot
  1 sibling, 0 replies; 8+ messages in thread
From: kernel test robot @ 2022-05-05 21:06 UTC (permalink / raw)
  To: Thomas Zimmermann, airlied, jfalempe, daniel
  Cc: llvm, kbuild-all, dri-devel, Thomas Zimmermann

Hi Thomas,

I love your patch! Perhaps something to improve:

[auto build test WARNING on drm/drm-next]
[also build test WARNING on drm-exynos/exynos-drm-next drm-intel/for-linux-next drm-tip/drm-tip tegra-drm/drm/tegra/for-next v5.18-rc5 next-20220505]
[cannot apply to airlied/drm-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/intel-lab-lkp/linux/commits/Thomas-Zimmermann/drm-mgag200-Fail-on-I2C-initialization-errors/20220505-234643
base:   git://anongit.freedesktop.org/drm/drm drm-next
config: i386-randconfig-a013 (https://download.01.org/0day-ci/archive/20220506/202205060439.bfJ2FmzU-lkp@intel.com/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 5e004fb787698440a387750db7f8028e7cb14cfc)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/11682b9fc557a02edac08b0dedc91ce704c2f749
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Thomas-Zimmermann/drm-mgag200-Fail-on-I2C-initialization-errors/20220505-234643
        git checkout 11682b9fc557a02edac08b0dedc91ce704c2f749
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash drivers/gpu/drm/mgag200/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> drivers/gpu/drm/mgag200/mgag200_mode.c:819:47: warning: variable 'ret' is uninitialized when used here [-Wuninitialized]
                   drm_err(dev, "failed to add DDC bus: %d\n", ret);
                                                               ^~~
   include/drm/drm_print.h:438:46: note: expanded from macro 'drm_err'
           __drm_printk((drm), err,, "*ERROR* " fmt, ##__VA_ARGS__)
                                                       ^~~~~~~~~~~
   include/drm/drm_print.h:425:48: note: expanded from macro '__drm_printk'
           dev_##level##type((drm)->dev, "[drm] " fmt, ##__VA_ARGS__)
                                                         ^~~~~~~~~~~
   include/linux/dev_printk.h:144:65: note: expanded from macro 'dev_err'
           dev_printk_index_wrap(_dev_err, KERN_ERR, dev, dev_fmt(fmt), ##__VA_ARGS__)
                                                                          ^~~~~~~~~~~
   include/linux/dev_printk.h:110:23: note: expanded from macro 'dev_printk_index_wrap'
                   _p_func(dev, fmt, ##__VA_ARGS__);                       \
                                       ^~~~~~~~~~~
   drivers/gpu/drm/mgag200/mgag200_mode.c:815:9: note: initialize the variable 'ret' to silence this warning
           int ret;
                  ^
                   = 0
   1 warning generated.


vim +/ret +819 drivers/gpu/drm/mgag200/mgag200_mode.c

   808	
   809	static int mgag200_vga_connector_init(struct mga_device *mdev)
   810	{
   811		struct drm_device *dev = &mdev->base;
   812		struct mga_connector *mconnector = &mdev->connector;
   813		struct drm_connector *connector = &mconnector->base;
   814		struct mga_i2c_chan *i2c;
   815		int ret;
   816	
   817		i2c = mgag200_i2c_create(dev);
   818		if (IS_ERR(i2c)) {
 > 819			drm_err(dev, "failed to add DDC bus: %d\n", ret);
   820			return PTR_ERR(i2c);
   821		}
   822	
   823		ret = drm_connector_init_with_ddc(dev, connector,
   824						  &mga_vga_connector_funcs,
   825						  DRM_MODE_CONNECTOR_VGA,
   826						  &i2c->adapter);
   827		if (ret)
   828			goto err_mgag200_i2c_destroy;
   829		drm_connector_helper_add(connector, &mga_vga_connector_helper_funcs);
   830	
   831		mconnector->i2c = i2c;
   832	
   833		return 0;
   834	
   835	err_mgag200_i2c_destroy:
   836		mgag200_i2c_destroy(i2c);
   837		return ret;
   838	}
   839	

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp

^ permalink raw reply	[flat|nested] 8+ messages in thread
* Re: [PATCH] drm/mgag200: Fail on I2C initialization errors
@ 2022-05-05 21:06   ` kernel test robot
  0 siblings, 0 replies; 8+ messages in thread
From: kernel test robot @ 2022-05-05 21:06 UTC (permalink / raw)
  To: Thomas Zimmermann, airlied, jfalempe, daniel
  Cc: llvm, kbuild-all, Thomas Zimmermann, dri-devel

Hi Thomas,

I love your patch! Perhaps something to improve:

[auto build test WARNING on drm/drm-next]
[also build test WARNING on drm-exynos/exynos-drm-next drm-intel/for-linux-next drm-tip/drm-tip tegra-drm/drm/tegra/for-next v5.18-rc5 next-20220505]
[cannot apply to airlied/drm-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/intel-lab-lkp/linux/commits/Thomas-Zimmermann/drm-mgag200-Fail-on-I2C-initialization-errors/20220505-234643
base:   git://anongit.freedesktop.org/drm/drm drm-next
config: i386-randconfig-a013 (https://download.01.org/0day-ci/archive/20220506/202205060439.bfJ2FmzU-lkp@intel.com/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 5e004fb787698440a387750db7f8028e7cb14cfc)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/11682b9fc557a02edac08b0dedc91ce704c2f749
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Thomas-Zimmermann/drm-mgag200-Fail-on-I2C-initialization-errors/20220505-234643
        git checkout 11682b9fc557a02edac08b0dedc91ce704c2f749
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash drivers/gpu/drm/mgag200/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> drivers/gpu/drm/mgag200/mgag200_mode.c:819:47: warning: variable 'ret' is uninitialized when used here [-Wuninitialized]
                   drm_err(dev, "failed to add DDC bus: %d\n", ret);
                                                               ^~~
   include/drm/drm_print.h:438:46: note: expanded from macro 'drm_err'
           __drm_printk((drm), err,, "*ERROR* " fmt, ##__VA_ARGS__)
                                                       ^~~~~~~~~~~
   include/drm/drm_print.h:425:48: note: expanded from macro '__drm_printk'
           dev_##level##type((drm)->dev, "[drm] " fmt, ##__VA_ARGS__)
                                                         ^~~~~~~~~~~
   include/linux/dev_printk.h:144:65: note: expanded from macro 'dev_err'
           dev_printk_index_wrap(_dev_err, KERN_ERR, dev, dev_fmt(fmt), ##__VA_ARGS__)
                                                                          ^~~~~~~~~~~
   include/linux/dev_printk.h:110:23: note: expanded from macro 'dev_printk_index_wrap'
                   _p_func(dev, fmt, ##__VA_ARGS__);                       \
                                       ^~~~~~~~~~~
   drivers/gpu/drm/mgag200/mgag200_mode.c:815:9: note: initialize the variable 'ret' to silence this warning
           int ret;
                  ^
                   = 0
   1 warning generated.


vim +/ret +819 drivers/gpu/drm/mgag200/mgag200_mode.c

   808	
   809	static int mgag200_vga_connector_init(struct mga_device *mdev)
   810	{
   811		struct drm_device *dev = &mdev->base;
   812		struct mga_connector *mconnector = &mdev->connector;
   813		struct drm_connector *connector = &mconnector->base;
   814		struct mga_i2c_chan *i2c;
   815		int ret;
   816	
   817		i2c = mgag200_i2c_create(dev);
   818		if (IS_ERR(i2c)) {
 > 819			drm_err(dev, "failed to add DDC bus: %d\n", ret);
   820			return PTR_ERR(i2c);
   821		}
   822	
   823		ret = drm_connector_init_with_ddc(dev, connector,
   824						  &mga_vga_connector_funcs,
   825						  DRM_MODE_CONNECTOR_VGA,
   826						  &i2c->adapter);
   827		if (ret)
   828			goto err_mgag200_i2c_destroy;
   829		drm_connector_helper_add(connector, &mga_vga_connector_helper_funcs);
   830	
   831		mconnector->i2c = i2c;
   832	
   833		return 0;
   834	
   835	err_mgag200_i2c_destroy:
   836		mgag200_i2c_destroy(i2c);
   837		return ret;
   838	}
   839	

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp

^ permalink raw reply	[flat|nested] 8+ messages in thread
* Re: [PATCH] drm/mgag200: Fail on I2C initialization errors
  2022-05-05 15:22 [PATCH] drm/mgag200: Fail on I2C initialization errors Thomas Zimmermann
  2022-05-05 15:49 ` Jocelyn Falempe
@ 2022-05-06  7:26 ` Dan Carpenter
  1 sibling, 0 replies; 8+ messages in thread
From: kernel test robot @ 2022-05-06  2:25 UTC (permalink / raw)
  To: kbuild

[-- Attachment #1: Type: text/plain, Size: 4231 bytes --]

CC: kbuild-all(a)lists.01.org
BCC: lkp(a)intel.com
In-Reply-To: <20220505152244.413-1-tzimmermann@suse.de>
References: <20220505152244.413-1-tzimmermann@suse.de>
TO: Thomas Zimmermann <tzimmermann@suse.de>
TO: airlied(a)redhat.com
TO: jfalempe(a)redhat.com
TO: daniel(a)ffwll.ch
CC: Thomas Zimmermann <tzimmermann@suse.de>
CC: dri-devel(a)lists.freedesktop.org

Hi Thomas,

I love your patch! Perhaps something to improve:

[auto build test WARNING on drm/drm-next]
[also build test WARNING on drm-exynos/exynos-drm-next drm-intel/for-linux-next drm-tip/drm-tip tegra-drm/drm/tegra/for-next v5.18-rc5 next-20220505]
[cannot apply to airlied/drm-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/intel-lab-lkp/linux/commits/Thomas-Zimmermann/drm-mgag200-Fail-on-I2C-initialization-errors/20220505-234643
base:   git://anongit.freedesktop.org/drm/drm drm-next
:::::: branch date: 11 hours ago
:::::: commit date: 11 hours ago
config: i386-randconfig-m021 (https://download.01.org/0day-ci/archive/20220506/202205061008.eYVQWRSt-lkp(a)intel.com/config)
compiler: gcc-11 (Debian 11.2.0-20) 11.2.0

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

smatch warnings:
drivers/gpu/drm/mgag200/mgag200_mode.c:819 mgag200_vga_connector_init() error: uninitialized symbol 'ret'.

vim +/ret +819 drivers/gpu/drm/mgag200/mgag200_mode.c

414c453106255b1 Dave Airlie           2012-04-17  808  
81a15b9a65565dc Thomas Zimmermann     2020-05-07  809  static int mgag200_vga_connector_init(struct mga_device *mdev)
414c453106255b1 Dave Airlie           2012-04-17  810  {
832eddf5d8f4d83 Thomas Zimmermann     2020-06-05  811  	struct drm_device *dev = &mdev->base;
81a15b9a65565dc Thomas Zimmermann     2020-05-07  812  	struct mga_connector *mconnector = &mdev->connector;
81a15b9a65565dc Thomas Zimmermann     2020-05-07  813  	struct drm_connector *connector = &mconnector->base;
81a15b9a65565dc Thomas Zimmermann     2020-05-07  814  	struct mga_i2c_chan *i2c;
81a15b9a65565dc Thomas Zimmermann     2020-05-07  815  	int ret;
414c453106255b1 Dave Airlie           2012-04-17  816  
81a15b9a65565dc Thomas Zimmermann     2020-05-07  817  	i2c = mgag200_i2c_create(dev);
11682b9fc557a02 Thomas Zimmermann     2022-05-05  818  	if (IS_ERR(i2c)) {
11682b9fc557a02 Thomas Zimmermann     2022-05-05 @819  		drm_err(dev, "failed to add DDC bus: %d\n", ret);
11682b9fc557a02 Thomas Zimmermann     2022-05-05  820  		return PTR_ERR(i2c);
11682b9fc557a02 Thomas Zimmermann     2022-05-05  821  	}
414c453106255b1 Dave Airlie           2012-04-17  822  
81a15b9a65565dc Thomas Zimmermann     2020-05-07  823  	ret = drm_connector_init_with_ddc(dev, connector,
9572ae176a10f3b Andrzej Pietrasiewicz 2019-07-26  824  					  &mga_vga_connector_funcs,
9572ae176a10f3b Andrzej Pietrasiewicz 2019-07-26  825  					  DRM_MODE_CONNECTOR_VGA,
81a15b9a65565dc Thomas Zimmermann     2020-05-07  826  					  &i2c->adapter);
81a15b9a65565dc Thomas Zimmermann     2020-05-07  827  	if (ret)
81a15b9a65565dc Thomas Zimmermann     2020-05-07  828  		goto err_mgag200_i2c_destroy;
414c453106255b1 Dave Airlie           2012-04-17  829  	drm_connector_helper_add(connector, &mga_vga_connector_helper_funcs);
414c453106255b1 Dave Airlie           2012-04-17  830  
81a15b9a65565dc Thomas Zimmermann     2020-05-07  831  	mconnector->i2c = i2c;
3d5a1c5e300483d Egbert Eich           2013-07-17  832  
81a15b9a65565dc Thomas Zimmermann     2020-05-07  833  	return 0;
81a15b9a65565dc Thomas Zimmermann     2020-05-07  834  
81a15b9a65565dc Thomas Zimmermann     2020-05-07  835  err_mgag200_i2c_destroy:
81a15b9a65565dc Thomas Zimmermann     2020-05-07  836  	mgag200_i2c_destroy(i2c);
81a15b9a65565dc Thomas Zimmermann     2020-05-07  837  	return ret;
414c453106255b1 Dave Airlie           2012-04-17  838  }
414c453106255b1 Dave Airlie           2012-04-17  839  

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp

^ permalink raw reply	[flat|nested] 8+ messages in thread
* Re: [PATCH] drm/mgag200: Fail on I2C initialization errors
@ 2022-05-06  7:26 ` Dan Carpenter
  0 siblings, 0 replies; 8+ messages in thread
From: Dan Carpenter @ 2022-05-06  7:26 UTC (permalink / raw)
  To: kbuild, Thomas Zimmermann, airlied, jfalempe, daniel
  Cc: dri-devel, kbuild-all, lkp, Thomas Zimmermann

Hi Thomas,

url:    https://github.com/intel-lab-lkp/linux/commits/Thomas-Zimmermann/drm-mgag200-Fail-on-I2C-initialization-errors/20220505-234643
base:   git://anongit.freedesktop.org/drm/drm drm-next
config: i386-randconfig-m021 (https://download.01.org/0day-ci/archive/20220506/202205061008.eYVQWRSt-lkp@intel.com/config)
compiler: gcc-11 (Debian 11.2.0-20) 11.2.0

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

smatch warnings:
drivers/gpu/drm/mgag200/mgag200_mode.c:819 mgag200_vga_connector_init() error: uninitialized symbol 'ret'.

vim +/ret +819 drivers/gpu/drm/mgag200/mgag200_mode.c

81a15b9a65565dc Thomas Zimmermann     2020-05-07  809  static int mgag200_vga_connector_init(struct mga_device *mdev)
414c453106255b1 Dave Airlie           2012-04-17  810  {
832eddf5d8f4d83 Thomas Zimmermann     2020-06-05  811  	struct drm_device *dev = &mdev->base;
81a15b9a65565dc Thomas Zimmermann     2020-05-07  812  	struct mga_connector *mconnector = &mdev->connector;
81a15b9a65565dc Thomas Zimmermann     2020-05-07  813  	struct drm_connector *connector = &mconnector->base;
81a15b9a65565dc Thomas Zimmermann     2020-05-07  814  	struct mga_i2c_chan *i2c;
81a15b9a65565dc Thomas Zimmermann     2020-05-07  815  	int ret;
414c453106255b1 Dave Airlie           2012-04-17  816  
81a15b9a65565dc Thomas Zimmermann     2020-05-07  817  	i2c = mgag200_i2c_create(dev);
11682b9fc557a02 Thomas Zimmermann     2022-05-05  818  	if (IS_ERR(i2c)) {
11682b9fc557a02 Thomas Zimmermann     2022-05-05 @819  		drm_err(dev, "failed to add DDC bus: %d\n", ret);
                                                                                                            ^^^
Uninitialized

11682b9fc557a02 Thomas Zimmermann     2022-05-05  820  		return PTR_ERR(i2c);
11682b9fc557a02 Thomas Zimmermann     2022-05-05  821  	}
414c453106255b1 Dave Airlie           2012-04-17  822  
81a15b9a65565dc Thomas Zimmermann     2020-05-07  823  	ret = drm_connector_init_with_ddc(dev, connector,
9572ae176a10f3b Andrzej Pietrasiewicz 2019-07-26  824  					  &mga_vga_connector_funcs,
9572ae176a10f3b Andrzej Pietrasiewicz 2019-07-26  825  					  DRM_MODE_CONNECTOR_VGA,
81a15b9a65565dc Thomas Zimmermann     2020-05-07  826  					  &i2c->adapter);
81a15b9a65565dc Thomas Zimmermann     2020-05-07  827  	if (ret)
81a15b9a65565dc Thomas Zimmermann     2020-05-07  828  		goto err_mgag200_i2c_destroy;
414c453106255b1 Dave Airlie           2012-04-17  829  	drm_connector_helper_add(connector, &mga_vga_connector_helper_funcs);
414c453106255b1 Dave Airlie           2012-04-17  830  
81a15b9a65565dc Thomas Zimmermann     2020-05-07  831  	mconnector->i2c = i2c;
3d5a1c5e300483d Egbert Eich           2013-07-17  832  
81a15b9a65565dc Thomas Zimmermann     2020-05-07  833  	return 0;
81a15b9a65565dc Thomas Zimmermann     2020-05-07  834  
81a15b9a65565dc Thomas Zimmermann     2020-05-07  835  err_mgag200_i2c_destroy:
81a15b9a65565dc Thomas Zimmermann     2020-05-07  836  	mgag200_i2c_destroy(i2c);
81a15b9a65565dc Thomas Zimmermann     2020-05-07  837  	return ret;
414c453106255b1 Dave Airlie           2012-04-17  838  }

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp


^ permalink raw reply	[flat|nested] 8+ messages in thread
* Re: [PATCH] drm/mgag200: Fail on I2C initialization errors
@ 2022-05-06  7:26 ` Dan Carpenter
  0 siblings, 0 replies; 8+ messages in thread
From: Dan Carpenter @ 2022-05-06  7:26 UTC (permalink / raw)
  To: kbuild-all

[-- Attachment #1: Type: text/plain, Size: 3335 bytes --]

Hi Thomas,

url:    https://github.com/intel-lab-lkp/linux/commits/Thomas-Zimmermann/drm-mgag200-Fail-on-I2C-initialization-errors/20220505-234643
base:   git://anongit.freedesktop.org/drm/drm drm-next
config: i386-randconfig-m021 (https://download.01.org/0day-ci/archive/20220506/202205061008.eYVQWRSt-lkp(a)intel.com/config)
compiler: gcc-11 (Debian 11.2.0-20) 11.2.0

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

smatch warnings:
drivers/gpu/drm/mgag200/mgag200_mode.c:819 mgag200_vga_connector_init() error: uninitialized symbol 'ret'.

vim +/ret +819 drivers/gpu/drm/mgag200/mgag200_mode.c

81a15b9a65565dc Thomas Zimmermann     2020-05-07  809  static int mgag200_vga_connector_init(struct mga_device *mdev)
414c453106255b1 Dave Airlie           2012-04-17  810  {
832eddf5d8f4d83 Thomas Zimmermann     2020-06-05  811  	struct drm_device *dev = &mdev->base;
81a15b9a65565dc Thomas Zimmermann     2020-05-07  812  	struct mga_connector *mconnector = &mdev->connector;
81a15b9a65565dc Thomas Zimmermann     2020-05-07  813  	struct drm_connector *connector = &mconnector->base;
81a15b9a65565dc Thomas Zimmermann     2020-05-07  814  	struct mga_i2c_chan *i2c;
81a15b9a65565dc Thomas Zimmermann     2020-05-07  815  	int ret;
414c453106255b1 Dave Airlie           2012-04-17  816  
81a15b9a65565dc Thomas Zimmermann     2020-05-07  817  	i2c = mgag200_i2c_create(dev);
11682b9fc557a02 Thomas Zimmermann     2022-05-05  818  	if (IS_ERR(i2c)) {
11682b9fc557a02 Thomas Zimmermann     2022-05-05 @819  		drm_err(dev, "failed to add DDC bus: %d\n", ret);
                                                                                                            ^^^
Uninitialized

11682b9fc557a02 Thomas Zimmermann     2022-05-05  820  		return PTR_ERR(i2c);
11682b9fc557a02 Thomas Zimmermann     2022-05-05  821  	}
414c453106255b1 Dave Airlie           2012-04-17  822  
81a15b9a65565dc Thomas Zimmermann     2020-05-07  823  	ret = drm_connector_init_with_ddc(dev, connector,
9572ae176a10f3b Andrzej Pietrasiewicz 2019-07-26  824  					  &mga_vga_connector_funcs,
9572ae176a10f3b Andrzej Pietrasiewicz 2019-07-26  825  					  DRM_MODE_CONNECTOR_VGA,
81a15b9a65565dc Thomas Zimmermann     2020-05-07  826  					  &i2c->adapter);
81a15b9a65565dc Thomas Zimmermann     2020-05-07  827  	if (ret)
81a15b9a65565dc Thomas Zimmermann     2020-05-07  828  		goto err_mgag200_i2c_destroy;
414c453106255b1 Dave Airlie           2012-04-17  829  	drm_connector_helper_add(connector, &mga_vga_connector_helper_funcs);
414c453106255b1 Dave Airlie           2012-04-17  830  
81a15b9a65565dc Thomas Zimmermann     2020-05-07  831  	mconnector->i2c = i2c;
3d5a1c5e300483d Egbert Eich           2013-07-17  832  
81a15b9a65565dc Thomas Zimmermann     2020-05-07  833  	return 0;
81a15b9a65565dc Thomas Zimmermann     2020-05-07  834  
81a15b9a65565dc Thomas Zimmermann     2020-05-07  835  err_mgag200_i2c_destroy:
81a15b9a65565dc Thomas Zimmermann     2020-05-07  836  	mgag200_i2c_destroy(i2c);
81a15b9a65565dc Thomas Zimmermann     2020-05-07  837  	return ret;
414c453106255b1 Dave Airlie           2012-04-17  838  }

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp

^ permalink raw reply	[flat|nested] 8+ messages in thread
* Re: [PATCH] drm/mgag200: Fail on I2C initialization errors
  2022-05-05 15:49 ` Jocelyn Falempe
@ 2022-05-06 10:53   ` Thomas Zimmermann
  0 siblings, 0 replies; 8+ messages in thread
From: Thomas Zimmermann @ 2022-05-06 10:53 UTC (permalink / raw)
  To: Jocelyn Falempe, airlied, daniel; +Cc: dri-devel


[-- Attachment #1.1: Type: text/plain, Size: 2985 bytes --]

Hi

Am 05.05.22 um 17:49 schrieb Jocelyn Falempe:
> On 05/05/2022 17:22, Thomas Zimmermann wrote:
>> Initialization of the I2C adapter was allowed to fail. The mgag200
>> driver would have continued without DDC support. Had this happened in
>> practice, it would have led to segmentation faults in the connector
>> code. Resolve this problem by failing driver initialization on I2C-
>> related errors.
> 
> Reviewed-by: Jocelyn Falempe <jfalempe@redhat.com>

Thanks a lot. I'll fix the reports from the automated tests and resubmit 
this patch as part of a larger patchset.

Best regards
Thomas

> 
>>
>> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
>> ---
>>   drivers/gpu/drm/mgag200/mgag200_i2c.c  | 13 ++++++++-----
>>   drivers/gpu/drm/mgag200/mgag200_mode.c |  6 ++++--
>>   2 files changed, 12 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/mgag200/mgag200_i2c.c 
>> b/drivers/gpu/drm/mgag200/mgag200_i2c.c
>> index ac8e34eef5138..31e2c641a7814 100644
>> --- a/drivers/gpu/drm/mgag200/mgag200_i2c.c
>> +++ b/drivers/gpu/drm/mgag200/mgag200_i2c.c
>> @@ -120,7 +120,7 @@ struct mga_i2c_chan *mgag200_i2c_create(struct 
>> drm_device *dev)
>>       i2c = kzalloc(sizeof(struct mga_i2c_chan), GFP_KERNEL);
>>       if (!i2c)
>> -        return NULL;
>> +        return ERR_PTR(-ENOMEM);
>>       i2c->data = data;
>>       i2c->clock = clock;
>> @@ -142,11 +142,14 @@ struct mga_i2c_chan *mgag200_i2c_create(struct 
>> drm_device *dev)
>>       i2c->bit.getscl        = mga_gpio_getscl;
>>       ret = i2c_bit_add_bus(&i2c->adapter);
>> -    if (ret) {
>> -        kfree(i2c);
>> -        i2c = NULL;
>> -    }
>> +    if (ret)
>> +        goto err_kfree;
>> +
>>       return i2c;
>> +
>> +err_kfree:
>> +    kfree(i2c);
>> +    return ERR_PTR(ret);
>>   }
>>   void mgag200_i2c_destroy(struct mga_i2c_chan *i2c)
>> diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c 
>> b/drivers/gpu/drm/mgag200/mgag200_mode.c
>> index abde7655477db..79557ca056f08 100644
>> --- a/drivers/gpu/drm/mgag200/mgag200_mode.c
>> +++ b/drivers/gpu/drm/mgag200/mgag200_mode.c
>> @@ -815,8 +815,10 @@ static int mgag200_vga_connector_init(struct 
>> mga_device *mdev)
>>       int ret;
>>       i2c = mgag200_i2c_create(dev);
>> -    if (!i2c)
>> -        drm_warn(dev, "failed to add DDC bus\n");
>> +    if (IS_ERR(i2c)) {
>> +        drm_err(dev, "failed to add DDC bus: %d\n", ret);
>> +        return PTR_ERR(i2c);
>> +    }
>>       ret = drm_connector_init_with_ddc(dev, connector,
>>                         &mga_vga_connector_funcs,
> 

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Ivo Totev

[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 840 bytes --]

^ permalink raw reply	[flat|nested] 8+ messages in thread
end of thread, other threads:[~2022-05-06 10:53 UTC | newest]

Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-05-05 15:22 [PATCH] drm/mgag200: Fail on I2C initialization errors Thomas Zimmermann
2022-05-05 15:49 ` Jocelyn Falempe
2022-05-06 10:53   ` Thomas Zimmermann
2022-05-05 21:06 ` kernel test robot
2022-05-05 21:06   ` kernel test robot
2022-05-06  2:25 kernel test robot
2022-05-06  7:26 ` Dan Carpenter
2022-05-06  7:26 ` Dan Carpenter

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.