Re: [PREEMPT_RT] 8250 IRQ lockup when flooding serial console (was Re: [ANNOUNCE] v5.4.28-rt19)

From: Steven Rostedt
Date: Thu Apr 23 2020 - 14:34:42 EST


On Thu, 23 Apr 2020 09:06:01 -0400
Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> BTW, I haven't released a new 5.4-rt because the default one is triggering
> a large latency somewhere, and makes my tests fail. I'm trying to dig into
> the cause when I get time.

Figured it out. Seems that starting with 5.4-rt, PREEMPT_RT now depends on
CONFIG_EXPERT, which I didn't have set, and PREEMPT_RT was disabled when
using my default config.

Had to add CONFIG_EXPERT to my default config to make it work again.

Starting the tests over....

-- Steve