[soc:board-remove 200/200] drivers/mmc/host/sdhci-pxav2.c:318 sdhci_pxav2_probe() error: we previously assumed 'variant' could be null (see line 305)

[Dan Carpenter]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/soc/soc.git board-remove
head:   c12d647b0229f4d75a2973c9b4e79f9b53406426
commit: c12d647b0229f4d75a2973c9b4e79f9b53406426 [200/200] remaining pdata removal
config: parisc-randconfig-r073-20260819 (https://download.01.org/0day-ci/archive/20260819/202608191405.jP6epa63-lkp@intel.com/config)
compiler: hppa-linux-gcc (GCC) 8.5.0
smatch: v0.5.0-9187-g5189e3fb

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 at intel.com>
| Reported-by: Dan Carpenter <error27 at gmail.com>
| Closes: https://lore.kernel.org/r/202608191405.jP6epa63-lkp@intel.com/

smatch warnings:
drivers/mmc/host/sdhci-pxav2.c:318 sdhci_pxav2_probe() error: we previously assumed 'variant' could be null (see line 305)

vim +/variant +318 drivers/mmc/host/sdhci-pxav2.c

e41c48b4bcb3ce Doug Brown            2023-01-16  295  	clk_core = devm_clk_get_optional_enabled(dev, "core");
072f5e2c34a95b Binbin Zhou           2025-06-07  296  	if (IS_ERR(clk_core))
072f5e2c34a95b Binbin Zhou           2025-06-07  297  		return dev_err_probe(dev, PTR_ERR(clk_core),
072f5e2c34a95b Binbin Zhou           2025-06-07  298  				     "failed to enable core clock\n");
e41c48b4bcb3ce Doug Brown            2023-01-16  299  
9f5d71e4a78a02 Zhangfei Gao          2011-06-08  300  	host->quirks = SDHCI_QUIRK_BROKEN_ADMA
9f5d71e4a78a02 Zhangfei Gao          2011-06-08  301  		| SDHCI_QUIRK_BROKEN_TIMEOUT_VAL
9f5d71e4a78a02 Zhangfei Gao          2011-06-08  302  		| SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN;
9f5d71e4a78a02 Zhangfei Gao          2011-06-08  303  
dfe9746aed2d12 Doug Brown            2023-01-16  304  	variant = of_device_get_match_data(dev);
dfe9746aed2d12 Doug Brown            2023-01-16 @305  	if (variant)

This assumes "variant" can be NULL.

b650352dd3df36 Chris Ball            2012-04-10  306  		pdata = pxav2_get_mmc_pdata(dev);
dfe9746aed2d12 Doug Brown            2023-01-16  307  
9f5d71e4a78a02 Zhangfei Gao          2011-06-08  308  	if (pdata->flags & PXA_FLAG_CARD_PERMANENT) {
9f5d71e4a78a02 Zhangfei Gao          2011-06-08  309  		/* on-chip device */
9f5d71e4a78a02 Zhangfei Gao          2011-06-08  310  		host->quirks |= SDHCI_QUIRK_BROKEN_CARD_DETECTION;
9f5d71e4a78a02 Zhangfei Gao          2011-06-08  311  		host->mmc->caps |= MMC_CAP_NONREMOVABLE;
9f5d71e4a78a02 Zhangfei Gao          2011-06-08  312  	}
9f5d71e4a78a02 Zhangfei Gao          2011-06-08  313  
9f5d71e4a78a02 Zhangfei Gao          2011-06-08  314  	/* If slot design supports 8 bit data, indicate this to MMC. */
9f5d71e4a78a02 Zhangfei Gao          2011-06-08  315  	if (pdata->flags & PXA_FLAG_SD_8_BIT_CAPABLE_SLOT)
9f5d71e4a78a02 Zhangfei Gao          2011-06-08  316  		host->mmc->caps |= MMC_CAP_8_BIT_DATA;
9f5d71e4a78a02 Zhangfei Gao          2011-06-08  317  
dfe9746aed2d12 Doug Brown            2023-01-16 @318  	host->quirks |= variant->extra_quirks;
dfe9746aed2d12 Doug Brown            2023-01-16  319  	host->ops = variant->ops;

But later it's dereferenced without checking.

9f5d71e4a78a02 Zhangfei Gao          2011-06-08  320  
f35ca223882aa6 Doug Brown            2023-01-16  321  	/* Set up optional pinctrl for PXA168 SDIO IRQ fix */
f35ca223882aa6 Doug Brown            2023-01-16  322  	pxav2_host->pinctrl = devm_pinctrl_get(dev);
f35ca223882aa6 Doug Brown            2023-01-16  323  	if (!IS_ERR(pxav2_host->pinctrl)) {
f35ca223882aa6 Doug Brown            2023-01-16  324  		pxav2_host->pins_cmd_gpio = pinctrl_lookup_state(pxav2_host->pinctrl,
f35ca223882aa6 Doug Brown            2023-01-16  325  								 "state_cmd_gpio");
f35ca223882aa6 Doug Brown            2023-01-16  326  		if (IS_ERR(pxav2_host->pins_cmd_gpio))
f35ca223882aa6 Doug Brown            2023-01-16  327  			pxav2_host->pins_cmd_gpio = NULL;

--
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