while using pwm(P9_14) got Kernel error "PREEMPT SMP ARM ".

Aim: stop Kernel error: PREEMPT SMP ARM

**Describe the bug**
I am working on BeagleBone Black with Debian Os. when I use PWM then I got kernel error. I receive errors while I use PWM(P9_14). sometimes runs and sometimes not. can suggest to me when this thing is to occur. I was set to pin P9_14 to PWM using ```config-pin P9_14 pwm```.
```
Message from syslogd@beaglebone at Sep 3 07:51:49 ...
kernel:[ 2412.180927] Internal error: : 1028 [#1] PREEMPT SMP ARM
```

**To Reproduce**
1) CODE :
```
#include
#include
#include
#include

#define SS 1
#define CHANNEL 'A'

int pwm=0;
int duty=0;
void main()
{
int init = rc_pwm_init(SS,100);
printf("\ninit=%d\n",init);

while(1)
{

duty = rc_pwm_set_duty_ns(SS,CHANNEL,pwm);
printf("\nduty=%d pwm=%d \n",duty,pwm);
rc_usleep(5000000);
pwm+=1000;
if(pwm>3000000){pwm=3000000;}
}
int close = rc_pwm_cleanup (SS);
printf("\nclose=%d\n",close);

}
```
2) COMPILE : gcc pwm.c -l:librobotcontrol.so.1 -o PWM
3) RUN : ./PWm
4) ERROR:
```
Message from syslogd@beaglebone at Sep 3 08:14:48 ...
kernel:[ 858.905205] Internal error: : 1028 [#1] PREEMPT SMP ARM

Message from syslogd@beaglebone at Sep 3 08:14:48 ...
kernel:[ 858.999750] Process PWM (pid: 2574, stack limit = 0xd799be38)

Message from syslogd@beaglebone at Sep 3 08:14:48 ...
kernel:[ 859.005521] Stack: (0xdb225e10 to 0xdb226000)

Message from syslogd@beaglebone at Sep 3 08:14:48 ...
kernel:[ 859.009900] 5e00: 00989680 db225e6c da880880 c07a1918

Message from syslogd@beaglebone at Sep 3 08:14:48 ...
kernel:[ 859.018116] 5e20: da8808a0 00002710 00000000 db260910 db225e64 db225e40 c079ec30 c07a1924

Message from syslogd@beaglebone at Sep 3 08:14:48 ...
kernel:[ 859.026333] 5e40: c1506e08 00000000 dad4559c da880880 00000005 db212bc0 db225ea4 db225e68
Segmentation fault
debian@beaglebone:~$
Message from syslogd@beaglebone at Sep 3 08:14:48 ...
kernel:[ 859.034550] 5e60: c079f45c c079eb14 00002710 00989680 00002710 00000000 00000001 172d0e31

Message from syslogd@beaglebone at Sep 3 08:14:48 ...
kernel:[ 859.042767] 5e80: db225ed4 c079f3e0 db260900 00000003 00000000 db225f60 db225ebc db225ea8

Message from syslogd@beaglebone at Sep 3 08:14:48 ...
kernel:[ 859.050984] 5ea0: c08d65e8 c079f3ec c08d65c0 db260900 db225ed4 db225ec0 c03abb1c c08d65cc

Message from syslogd@beaglebone at Sep 3 08:14:48 ...
kernel:[ 859.059200] 5ec0: 00000005 db260900 db225f0c db225ed8 c03ab10c c03abae0 00000003 00000000

Message from syslogd@beaglebone at Sep 3 08:14:48 ...
kernel:[ 859.067416] 5ee0: dab1a588 c03ab014 db16a300 befac458 db225f60 00000000 00000000 00000004

Message from syslogd@beaglebone at Sep 3 08:14:48 ...
kernel:[ 859.075633] 5f00: db225f24 db225f10 c0319564 c03ab020 00000005 db16a300 db225f54 db225f28

Message from syslogd@beaglebone at Sep 3 08:14:48 ...
kernel:[ 859.083849] 5f20: c031976c c0319548 00000000 c033bd58 db16a300 c1506e08 db16a300 befac458

Message from syslogd@beaglebone at Sep 3 08:14:48 ...
kernel:[ 859.092065] 5f40: 00000003 00000000 db225f94 db225f58 c0319a4c c03196c4 00000003 00000000

Message from syslogd@beaglebone at Sep 3 08:14:48 ...
kernel:[ 859.100281] 5f60: 00000003 00000000 00000000 172d0e31 00000074 b6ef3000 00000041 00000004

Message from syslogd@beaglebone at Sep 3 08:14:48 ...
kernel:[ 859.108497] 5f80: c0101204 db224000 db225fa4 db225f98 c0319ad8 c03199e4 00000000 db225fa8

Message from syslogd@beaglebone at Sep 3 08:14:48 ...
kernel:[ 859.116714] 5fa0: c0101000 c0319acc 00000074 b6ef3000 00000003 befac458 00000005 00000000

Message from syslogd@beaglebone at Sep 3 08:14:48 ...
kernel:[ 859.124930] 5fc0: 00000074 b6ef3000 00000041 00000004 00000000 00000000 00414000 00000000

Message from syslogd@beaglebone at Sep 3 08:14:48 ...
kernel:[ 859.133146] 5fe0: 00000004 befac438 b6e405b3 b6dc9746 600f0030 00000003 00000000 00000000

Message from syslogd@beaglebone at Sep 3 08:14:48 ...
kernel:[ 859.246154] Code: e5940000 eb0524e7 e594a02c e6ff7077 (e1da30b0)

```

**Platform information**
debian@beaglebone:~$ cat /etc/issue
Debian GNU/Linux 10 \n \l

BeagleBoard.org Debian Buster IoT Image 2020-04-06

Support: http://elinux.org/Beagleboard:BeagleBoneBlack_Debian

default username:password is [debian:temppwd]

debian@beaglebone:~$ cat /proc/version

Linux version 4.19.94-ti-r42 (voodoo@x3-am57xx-beagle-x15-2gb) (gcc version 8.3.0 (Debian 8.3.0-6)) #1buster SMP PREEMPT Tue Mar 31 19:38:29 UTC 2020