Re: [PATCH] drm: gud: replace WARN_ON/WARN_ON_ONCE with drm versions

[Dan Carpenter <dan.carpenter@linaro.org>]

Hi Ruben,

kernel test robot noticed the following build warnings:

https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Ruben-Wauters/drm-gud-replace-WARN_ON-WARN_ON_ONCE-with-drm-versions/20250914-235627
base:   git://anongit.freedesktop.org/drm/drm-misc drm-misc-next
patch link:    https://lore.kernel.org/r/20250914155308.2144-1-rubenru09%40aol.com
patch subject: [PATCH] drm: gud: replace WARN_ON/WARN_ON_ONCE with drm versions
config: x86_64-randconfig-161-20250921 (https://download.01.org/0day-ci/archive/20250921/202509212215.c8v3RKmL-lkp@intel.com/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)

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/202509212215.c8v3RKmL-lkp@intel.com/

smatch warnings:
drivers/gpu/drm/gud/gud_connector.c:597 gud_connector_fill_properties() warn: passing a valid pointer to 'PTR_ERR'

vim +/PTR_ERR +597 drivers/gpu/drm/gud/gud_connector.c

40e1a70b4aedf2 Noralf Trønnes 2021-03-13  580  int gud_connector_fill_properties(struct drm_connector_state *connector_state,
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  581  				  struct gud_property_req *properties)
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  582  {
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  583  	struct gud_connector *gconn = to_gud_connector(connector_state->connector);
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  584  	unsigned int i;
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  585  
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  586  	for (i = 0; i < gconn->num_properties; i++) {
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  587  		u16 prop = gconn->properties[i];
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  588  		u64 val;
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  589  
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  590  		if (prop == GUD_PROPERTY_BACKLIGHT_BRIGHTNESS) {
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  591  			val = connector_state->tv.brightness;
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  592  		} else {
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  593  			unsigned int *state_val;
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  594  
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  595  			state_val = gud_connector_tv_state_val(prop, &connector_state->tv);
d00e57106c0d0c Ruben Wauters  2025-09-14  596  			if (drm_WARN_ON_ONCE(connector_state->connector->dev, state_val))

You accidentally deleted the IS_ERR() check so now this function is
badly broken.

	if (drm_WARN_ON_ONCE(connector_state->connector->dev, IS_ERR(state_val)))

40e1a70b4aedf2 Noralf Trønnes 2021-03-13 @597  				return PTR_ERR(state_val);
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  598  
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  599  			val = *state_val;
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  600  		}
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  601  
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  602  		properties[i].prop = cpu_to_le16(prop);
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  603  		properties[i].val = cpu_to_le64(val);
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  604  	}
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  605  
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  606  	return gconn->num_properties;
40e1a70b4aedf2 Noralf Trønnes 2021-03-13  607  }

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