Subject: Re: [PATCH net-next 1/1] net: wwan: t7xx: Add port for modem logging

From: Jakub Kicinski <[email-masked]>
Date: Fri, 20 May 2022 10:48:14 -0700

On Fri, 20 May 2022 10:42:56 -0700 moises.veleta wrote:
> On 5/20/22 10:37, Jakub Kicinski wrote:
> > On Thu, 19 May 2022 11:27:03 -0700 Moises Veleta wrote:  
> >> +	ret = copy_from_user(skb_put(skb, actual_len), buf, actual_len);
> >> +	if (ret) {
> >> +		ret = -EFAULT;
> >> +		goto err_out;
> >> +	}
> >> +
> >> +	ret = t7xx_port_send_skb(port, skb, 0, 0);
> >> +	if (ret)
> >> +		goto err_out;  
> > We don't allow using debugfs to pass random data from user space
> > to firmware in networking. You need to find another way.  
> 
> 
> Can we use debugfs to send an "on" or "off" commands, wherein the driver 
> then sends special command sequences to the the firmware triggering the 
> modem logging on and off?

On/off for all logging or for particular types of messages?
If it's for all logging can't the act of opening the debugfs 
file be used as on "on" signal and closing as "off"?

Where do the logging messages go?