MTTCAN - Sending of data results in a kernel NULL pointer

Hello,
we switched from an external can controller connected via SPI to the internal mttcan controller of the tx2. Reading data with candump works normally while trying to send data via cansend results in a null pointer dereference in the kernel driver.
Send and receive data via can1 works correctly.

~# cansend can0 123#deadbeef
[ 3772.197203] Unable to handle kernel NULL pointer dereference at virtual address 00000008
[ 3772.205309] pgd = ffffffc000b53000
[ 3772.208727] [00000008] *pgd=0000000276641003root@afc-ecu-tx2:~#, *pud=0000000276641003 , *pmd=0000000276642003, *pte=00e8000003881707
[ 3772.222169] Internal error: Oops: 96000005 [#1] PREEMPT SMP
[ 3772.227738] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.4.38+ #14
[ 3772.233825] Hardware name: afc-ecu (DT)
[ 3772.237659] task: ffffffc000a119a0 ti: ffffffc000a04000 task.ti: ffffffc000a04000
[ 3772.245142] PC is at timecounter_cyc2time+0xc/0x58
[ 3772.249935] LR is at mttcan_poll_ir+0x848/0xad8
[ 3772.254462] pc : [<ffffffc0001002e4>] lr : [<ffffffc00064ad60>] pstate: 60000045
[ 3772.261849] sp : ffffffc000a07b00
[ 3772.265161] x29: ffffffc000a07b00 x28: ffffffc059339b20 
[ 3772.270489] x27: ffffffc000a07b90 x26: ffffffc000a07b90 
[ 3772.275816] x25: ffffffc000a07b90 x24: ffffffc059339b08 
[ 3772.281142] x23: 0000000000000000 x22: ffffffc059339800 
[ 3772.286468] x21: 0000000000001200 x20: 0000000000000000 
[ 3772.291793] x19: ffffffc059339000 x18: 000000000000000a 
[ 3772.297118] x17: 00000000004dc458 x16: ffffffc00017f168 
[ 3772.302444] x15: 0000007fb4759028 x14: 0000003fffffffff 
[ 3772.307768] x13: 0000003fffffffff x12: 0000000000000000 
[ 3772.313093] x11: 0000000000000000 x10: 0000000000000810 
[ 3772.318418] x9 : 0000000000000000 x8 : ffffffc07b2e7d80 
[ 3772.323743] x7 : 0000000000000000 x6 : 0000000000000000 
[ 3772.329067] x5 : 0000000000000000 x4 : 0000000000000000 
[ 3772.334392] x3 : ffffffc07b2e7d80 x2 : 0000000000c38f70 
[ 3772.339719] x1 : 000000000000efd8 x0 : 0000000000000000
[ 3772.345044] 
[ 3772.346537] Process swapper/0 (pid: 0, stack limit = 0xffffffc000a04020)
[ 3772.353229] Call trace:
[ 3772.355678] [<ffffffc0001002e4>] timecounter_cyc2time+0xc/0x58
[ 3772.361507] [<ffffffc000671330>] net_rx_action+0x1c8/0x2a0
[ 3772.366990] [<ffffffc0000a3e88>] __do_softirq+0x100/0x208
[ 3772.372383] [<ffffffc0000a4210>] irq_exit+0x88/0xe0
[ 3772.377258] [<ffffffc0000e64e0>] __handle_domain_irq+0x60/0xb8
[ 3772.383085] [<ffffffc00008177c>] gic_handle_irq+0x64/0xc0
[ 3772.388479] [<ffffffc000084740>] el1_irq+0x80/0xf8
[ 3772.393270] [<ffffffc000590268>] cpuidle_enter+0x18/0x20
[ 3772.398579] [<ffffffc0000dc2a8>] cpu_startup_entry+0x1b8/0x208
[ 3772.404409] [<ffffffc000738ab8>] rest_init+0x88/0x98
[ 3772.409374] [<ffffffc0009aa94c>] start_kernel+0x380/0x394
[ 3772.414765] [<000000008073e000>] 0x8073e000
[ 3772.419234] ---[ end trace 60ca2b897443a1df ]---
[ 3772.425907] Kernel panic - not syncing: Fatal exception in interrupt

following is the devicetree entry of the nodes (can0=mttcan, can1=mcp2515 connected via spi):

mttcan@c310000 {
        status = "okay";
        gpio_can_stb = <&tegra_aon_gpio TEGRA_AON_GPIO(AA, 0) GPIO_ACTIVE_HIGH>;
        gpio_can_en = <&tegra_aon_gpio TEGRA_AON_GPIO(AA, 1) GPIO_ACTIVE_HIGH>;
        mram-params = <0 16 16 8 8 8 16 16 16>;
        tx-config = <8 8 0 64>;
        rx-config = <64 64 64>;
    };

    mttcan@c320000 {
        status = "disabled";
    };

&spi0 {
        status = "okay";
        spi-max-frequency = <10000000>;
        nvidia,polling-mode;
	nvidia,clock-always-on;

        can1: can1@0 {
            compatible = "microchip,mcp2515";
            reg = <0x0>;
            interrupt-parent = <&tegra_main_gpio>;
            interrupts = <TEGRA_MAIN_GPIO(Y, 6) GPIO_ACTIVE_LOW>;
            spi-max-frequency = <10000000>;
            oscillator_frequency = <20000000>;
            nvidia,enable-hw-based-cs;
            clocks = <&clk20m>;
        };

};

The interfaces are enabled by:

ip link set can0 up type can bitrate 250000 restart-ms 100
ip link set can1 up type can bitrate 250000 restart-ms 100

Thank you for any help with this issue.