Re: [PATCH] [RFC] rt: kernel/sched/core: fix kthread_park() pending too long when CPU un-plugged

From: Sebastian Siewior
Date: Fri Jan 08 2021 - 04:05:53 EST


On 2021-01-08 08:45:14 [+0000], Ran Wang wrote:
> Hi Sebastian, Peter
Hi,

> > I had a similar patch in -RT and dropped it in v5.10-rc7-rt16.
> > It was added because RT couldn't boot since creating the boot-threads didn't work before the ksoftirqd was up. This was fixed by commit
> > 26c7295be0c5e ("kthread: Do not preempt current task if it is going to call schedule()")
>
> I tried applying above commit to linux-5.6.y-rt, it could resolve my problem on LX2160ARDB, THANKS!

so in other words all this could have been avoided by using a supported
or maintained RT series. The v5.4 series has this patch, v5.6 isn't
maintained anymore so it is likely that there is more missing.

Sebastian