If sdhci-omap is configured for an unused device instance and the device is not set as disabled, we can get a NULL pointer dereference: Unable to handle kernel NULL pointer dereference at virtual address 00000045 ... (regulator_set_voltage) from [<c07d7008>] (mmc_regulator_set_ocr+0x44/0xd0) (mmc_regulator_set_ocr) from [<c07e2d80>] (sdhci_set_ios+0xa4/0x490) (sdhci_set_ios) from [<c07ea690>] (sdhci_omap_set_ios+0x124/0x160) (sdhci_omap_set_ios) from [<c07c8e94>] (mmc_power_up.part.0+0x3c/0x154) (mmc_power_up.part.0) from [<c07c9d20>] (mmc_start_host+0x88/0x9c) (mmc_start_host) from [<c07cad34>] (mmc_add_host+0x58/0x7c) (mmc_add_host) from [<c07e2574>] (__sdhci_add_host+0xf0/0x22c) (__sdhci_add_host) from [<c07eaf68>] (sdhci_omap_probe+0x318/0x72c) (sdhci_omap_probe) from [<c06a39d8>] (platform_probe+0x58/0xb8) AFAIK we are not seeing this with the devices configured in the mainline kernel but this can cause issues for folks bringing up their boards. Fixes: 7d326930d352 ("mmc: sdhci-omap: Add OMAP SDHCI driver") Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx> --- drivers/mmc/host/sdhci-omap.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/mmc/host/sdhci-omap.c b/drivers/mmc/host/sdhci-omap.c --- a/drivers/mmc/host/sdhci-omap.c +++ b/drivers/mmc/host/sdhci-omap.c @@ -682,7 +682,8 @@ static void sdhci_omap_set_power(struct sdhci_host *host, unsigned char mode, { struct mmc_host *mmc = host->mmc; - mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, vdd); + if (!IS_ERR(mmc->supply.vmmc)) + mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, vdd); } static int sdhci_omap_enable_dma(struct sdhci_host *host) -- 2.33.0