Re: 4.14 backport request for dbdda842fe96f: "printk: Add console owner and waiter logic to load balance console writes"

From: Sergey Senozhatsky
Date: Wed Dec 12 2018 - 01:28:50 EST


On (12/11/18 22:08), Daniel Wang wrote:
>
> I've been meaning to try it but kept getting distracted by other
> things. I'll try to find some time for it this week or next. Right now
> my intent is to get Steven's patch into 4.14 stable as it evidently
> fixed the particular issue I was seeing, and as Steven said it has
> been in upstream since 4.16 so it's not like backporting it will raise
> any red flags. I will start another thread on -stable for it.

OK.

> > I guess we still don't have a really clear understanding of what exactly
> is going in your system
>
> I would also like to get to the bottom of it. Unfortunately I haven't
> got the expertise in this area nor the time to do it yet. Hence the
> intent to take a step back and backport Steven's patch to fix the
> issue that has resurfaced in our production recently.

No problem.
I just meant that -stable people can be a bit "unconvinced".

> Which two sets are you referring to specifically?

I guess I used the wrong word:

The first set (actually just one patch) is the one that makes consoles
re-entrant from panic().
The other set - those 4 patches (Steven's patch, + Petr's patch + a
patch that makes printk() atomic again).

-ss