Re: [RFC PATCH 0/3] drm/log: Introduce a new boot logger to draw the kmsg on the screen

[John Ogness]

On 2024-08-01, Jocelyn Falempe <jfalempe@xxxxxxxxxx> wrote:
>  * I tried to use the new nbcon interface, but didn't get any message
>  from the write_atomic() callback, but the goal is to use that when
>  it's ready.

Be aware that the write_atomic() callback _must_ also print from NMI
context. write_thread() may be the callback you are interested
instead. Note that for CON_NBCON, write_atomic() is optional,
write_thread() is mandatory.

Disclaimer: All of this currently only available in the PREEMPT_RT
patchset. So until it hits mainline, semantics may yet change.

John Ogness