[linux-next:master 4298/8232] drivers/gpu/drm/panel/panel-sharp-lq101r1sx01.c:366 sharp_panel_remove() error: we previously assumed 'sharp' could be null (see line 365)

[linux-next:master 4298/8232] drivers/gpu/drm/panel/panel-sharp-lq101r1sx01.c:366 sharp_panel_remove() error: we previously assumed 'sharp' could be null (see line 365)

[Dan Carpenter]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
head:   0fc4bfab2cd45f9acb86c4f04b5191e114e901ed
commit: d7d473d8464e7b9931c0b19f68ea0df807e01b4c [4298/8232] drm/panel: sharp-lq101r1sx01: Don't call disable at shutdown/remove
config: x86_64-randconfig-161-20240626 (https://download.01.org/0day-ci/archive/20240626/202406261525.SkhtM3ZV-lkp@intel.com/config)
compiler: gcc-10 (Ubuntu 10.5.0-1ubuntu1) 10.5.0

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
| Closes: https://lore.kernel.org/r/202406261525.SkhtM3ZV-lkp@intel.com/

smatch warnings:
drivers/gpu/drm/panel/panel-sharp-lq101r1sx01.c:366 sharp_panel_remove() error: we previously assumed 'sharp' could be null (see line 365)

vim +/sharp +366 drivers/gpu/drm/panel/panel-sharp-lq101r1sx01.c

79abca2b399009 Uwe Kleine-König 2022-07-08  355  static void sharp_panel_remove(struct mipi_dsi_device *dsi)
1976dbca047ed7 Thierry Reding   2014-08-01  356  {
1976dbca047ed7 Thierry Reding   2014-08-01  357  	struct sharp_panel *sharp = mipi_dsi_get_drvdata(dsi);
1976dbca047ed7 Thierry Reding   2014-08-01  358  	int err;
1976dbca047ed7 Thierry Reding   2014-08-01  359  
1976dbca047ed7 Thierry Reding   2014-08-01  360  	err = mipi_dsi_detach(dsi);
1976dbca047ed7 Thierry Reding   2014-08-01  361  	if (err < 0)
1976dbca047ed7 Thierry Reding   2014-08-01  362  		dev_err(&dsi->dev, "failed to detach from DSI host: %d\n", err);
1976dbca047ed7 Thierry Reding   2014-08-01  363  
d7d473d8464e7b Douglas Anderson 2024-06-04  364  	/* only detach from host for the DSI-LINK2 interface */
1976dbca047ed7 Thierry Reding   2014-08-01 @365  	if (!sharp)

Reversed if statement?

d7d473d8464e7b Douglas Anderson 2024-06-04 @366  		sharp_panel_del(sharp);
1976dbca047ed7 Thierry Reding   2014-08-01  367  }

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [linux-next:master 4298/8232] drivers/gpu/drm/panel/panel-sharp-lq101r1sx01.c:366 sharp_panel_remove() error: we previously assumed 'sharp' could be null (see line 365)

[Doug Anderson]

Hi,

On Mon, Jul 1, 2024 at 8:45 AM Dan Carpenter <dan.carpenter@linaro.org> wrote:
>
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
> head:   0fc4bfab2cd45f9acb86c4f04b5191e114e901ed
> commit: d7d473d8464e7b9931c0b19f68ea0df807e01b4c [4298/8232] drm/panel: sharp-lq101r1sx01: Don't call disable at shutdown/remove
> config: x86_64-randconfig-161-20240626 (https://download.01.org/0day-ci/archive/20240626/202406261525.SkhtM3ZV-lkp@intel.com/config)
> compiler: gcc-10 (Ubuntu 10.5.0-1ubuntu1) 10.5.0
>
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
> | Closes: https://lore.kernel.org/r/202406261525.SkhtM3ZV-lkp@intel.com/
>
> smatch warnings:
> drivers/gpu/drm/panel/panel-sharp-lq101r1sx01.c:366 sharp_panel_remove() error: we previously assumed 'sharp' could be null (see line 365)
>
> vim +/sharp +366 drivers/gpu/drm/panel/panel-sharp-lq101r1sx01.c
>
> 79abca2b399009 Uwe Kleine-König 2022-07-08  355  static void sharp_panel_remove(struct mipi_dsi_device *dsi)
> 1976dbca047ed7 Thierry Reding   2014-08-01  356  {
> 1976dbca047ed7 Thierry Reding   2014-08-01  357         struct sharp_panel *sharp = mipi_dsi_get_drvdata(dsi);
> 1976dbca047ed7 Thierry Reding   2014-08-01  358         int err;
> 1976dbca047ed7 Thierry Reding   2014-08-01  359
> 1976dbca047ed7 Thierry Reding   2014-08-01  360         err = mipi_dsi_detach(dsi);
> 1976dbca047ed7 Thierry Reding   2014-08-01  361         if (err < 0)
> 1976dbca047ed7 Thierry Reding   2014-08-01  362                 dev_err(&dsi->dev, "failed to detach from DSI host: %d\n", err);
> 1976dbca047ed7 Thierry Reding   2014-08-01  363
> d7d473d8464e7b Douglas Anderson 2024-06-04  364         /* only detach from host for the DSI-LINK2 interface */
> 1976dbca047ed7 Thierry Reding   2014-08-01 @365         if (!sharp)
>
> Reversed if statement?
>
> d7d473d8464e7b Douglas Anderson 2024-06-04 @366                 sharp_panel_del(sharp);
> 1976dbca047ed7 Thierry Reding   2014-08-01  367  }

Indeed. Thanks for the catch. Fix posted at:

https://lore.kernel.org/r/20240708105221.1.I576751c661c7edb6b804dda405d10e2e71153e32@changeid