Kernel Panic

[chandraevolute]

I am using IMX6ULEVK board and 3.14.38 BSP version

Hi I am getting kernel panic, attached Log.txt is the boot log.

I wrote a small module as part of the kernel source tree. Switch.c is the module that I wanted to be loaded. It  will register the irq, whenever a switch press happens led should glow.

Below is my dts configurations for the pins I am using

&gpio3{

        interrupt-parent = <&gpio3>;

        interrupts = <22 8>;

};

&iomuxc {

        pinctrl-names = "default";

        pinctrl-0 = <&pinctrl_hog_1>;

        imx6ul-evk {

                pinctrl_hog_1: hoggrp-1 {

                        fsl,pins = <

                                MX6UL_PAD_LCD_RESET__WDOG1_WDOG_ANY    0x30b0

                                MX6UL_PAD_UART1_RTS_B__GPIO1_IO19       0x17059 /* SD1 CD */

                                MX6UL_PAD_GPIO1_IO05__USDHC1_VSELECT    0x17059 /* SD1 VSELECT */

                                MX6UL_PAD_GPIO1_IO09__GPIO1_IO09        0x17059 /* SD1 RESET */

                                MX6UL_PAD_LCD_DATA16__GPIO3_IO21        0x010B0

                        >;

                };

the bold ones I have added.

why kernel panic is happening and also you can observe in the log below line. why the gpiod_direction_output is invalid gpio.

GPIO_TEST: Initializing the GPIO_TEST LKM

gpiod_direction_output: invalid GPIO

gpiod_direction_input: invalid GPIO

gpiod_set_debounce: invalid GPIO

Original Attachment has been moved to: Switch.c.zip

Original Attachment has been moved to: Log.txt.zip

[igorpadykov · Accepted solution]

HI chandra

one can check if LCD_DATA16 is already used as output

MX6UL_PAD_LCD_DATA16__LCDIF_DATA16 in uboot mx6ul_14x14_evk.c lcd_pads[] :

uboot-imx.git - Freescale i.MX u-boot Tree

and imx6ul-14x14-evk.dts pinctrl_lcdif_dat: lcdifdatgrp :

linux-2.6-imx.git - Freescale i.MX Linux Tree

Best regards

igor

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[chandraevolute]

Hi igo,

     I commented LCD data pins in uboot mx6ul_14x14_evk.c lcd_pads[] and also removed all the LCD based entries in dts and dtsi file. still the problem is present

usbcore: registered new interface driver usbhid

usbhid: USB HID core driver

GPIO_TEST: Initializing the GPIO_TEST LKM

gpiod_direction_output: invalid GPIO

gpiod_direction_input: invalid GPIO

gpiod_set_debounce: invalid GPIO

Unable to handle kernel NULL pointer dereference at virtual address 0000004c

pgd = 80004000

[0000004c] *pgd=00000000

Internal error: Oops: 5 [#1] PREEMPT SMP ARM

Modules linked in:

CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.14.38-6UL_ga+ge4944a5 #6

task: 88058000 ti: 8805c000 task.ti: 8805c000

PC is at gpiod_get_raw_value+0x14/0x7c

LR is at ebbgpio_init+0xa0/0x11c

pc : [<802b54d8>]    lr : [<808ae29c>]    psr: a0000113

sp : 8805ded8  ip : f42c407c  fp : 00000000

r10: 808bca44  r9 : 000000d3  r8 : 8091c680

r7 : 00000001  r6 : 00000001  r5 : 80798760  r4 : 8096dde8

r3 : 00000000  r2 : 00000001  r1 : 00000000  r0 : 00000000

Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel

Regards,

Chandra

[igorpadykov]

Hi Chandra

could you remove custom module to check

if error "Unable to handle kernel NULL pointer dereference"

was caused by that module (probably due to wrong building).

~igor

[chandraevolute]

i am able to handle it