printk_devkmsg

file: /proc/sys/kernel/printk_devkmsg
variable: kernel.printk_devkmsg
Official reference

Control the logging to /dev/kmsg from userspace:

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ratelimit default, ratelimited
on        unlimited logging to /dev/kmsg from userspace
off       logging to /dev/kmsg disabled
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The kernel command line parameter printk.devkmsg= overrides this and is a one-time setting until next reboot: once set, it cannot be changed by this sysctl interface anymore.

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