IOCTL Failed to with netdevice SIOCDEVPRIVATE in IMX8M Mini with Linux Kernel 5.15

[RajendraPrasadBhoga]

Dear Team,

I have written a sample kernel driver and user space application and tried IOCTL Call to SIOCDEVPRIVATE address which not working and showing below error

Start...
ioctl error -1, err: Operation not supported
Finished...

5.15 kernel version used here.

Same code is working on another device with kernel version 4.19 

Could you please get back what might be the issue ? We tried IOR , IOW, IOWR calls also but the same issue ?

kernel space part of where ioctl call has to happen

#define SIOC_CHRIZ SIOCDEVPRIVATE+14

static int chriz_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
{
printk(KERN_INFO "chriz ioctl: command: %x\n", cmd);
return 0;
}

User space part

#define SIOC_CHRIZ SIOCDEVPRIVATE+14

int main() {

int sock = 0;
int ret = 0;

struct iwreq iwr;
struct ifreq ifr;

printf("Start...\n");

// init net socket
sock = socket(AF_INET, SOCK_DGRAM, 0);
if (sock < 0) {
printf("socket error\n");
return 1;
}

// fill in interface name
memset(&iwr, 0, sizeof(iwr)); // for wireless
strcpy(iwr.ifr_name, interface_name);
memset(&ifr, 0, sizeof(ifr)); // for ethernet
strcpy(ifr.ifr_name, interface_name);

// do ioctl
ret = ioctl(sock, SIOC_CHRIZ, &ifr);
if (ret < 0) {
printf("ioctl error %d, err: %s\n", ret, strerror(errno));
}

// finished
printf("Finished...\n");
close(sock);
return 0;

}

[mskerritt]

Check out this posting, which I think is your issue:

https://stackoverflow.com/questions/73079492/has-there-been-any-change-between-kernel-5-15-and-5-4-0...

[Manuel_Salas]

Hello @RajendraPrasadBhoga ,

Could you please try close(sock) before ret = ioctl(sock, SIOC_CHRIZ, &ifr)

// do ioctl
pclose(sock);
ret = ioctl(sock, SIOC_CHRIZ, &ifr);
if (ret < 0) {
printf("ioctl error %d, err: %s\n", ret, strerror(errno));
}


// finished
printf("Finished...\n");

return 0;

(note the change of close to pclose)

Let me know hot it was!

Best regards.

[mskerritt]

Check out this post:
https://stackoverflow.com/questions/73079492/has-there-been-any-change-between-kernel-5-15-and-5-4-0...