Re: printk: Add kernel parameter to disable writes to /dev/kmsg

[Pavel Machek]

On Mon 2016-04-25 13:06:29, Steven Rostedt wrote:
> Over the weekend my server was acting funny. The display wasn't working
> well, and I assumed that a driver was going bad. I went to look at the
> kernel dmesg, but the buffer only had the following over and over:
> 
> [226062.401405] systemd-logind[3511]: Removed session 4168.
> [226063.381051] systemd-logind[3511]: Removed session 4169.

systemd has root. I'm not sure additional parameter to fight it is
good idea. What's next? systemd evolves a way to override kernel
parameters? :-)

> I simply propose a way to let us kernel developers keep user space from
> interfering, by adding a new kernel command line parameter that will
> disable writing to /dev/kmsg. Any attempt to open the file in write
> mode will return a -EPERM error.

chmod 400 /dev/kmsg? With udev, it should be possible to make it persistent...

									Pavel

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