Re: Strange output on the console
From: Sergey Senozhatsky
Date: Fri Feb 25 2022 - 00:07:20 EST
On (22/02/25 13:58), Sergey Senozhatsky wrote:
> On (22/02/24 23:00), Steven Rostedt wrote:
> > I've been noticing that my tests have been spitting out strange output on
> > the console. It would happen at boot up and then clear up. It looks like
> > something screwed up with the serial timing.
> >
> > Attached is a dmesg of one of my test runs as an example.
> >
> > I've noticed this on both 32 bit and 64 bit x86.
> >
> > I haven't had time to look deeper into this, but I figured I let you know
> > about it.
> >
> > And it always seems to happen right after:
> >
> > Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
> >
> > Maybe this is a serial issue and not a printk one? :-/
>
> Steven, did you notice this recently?
> May I perhaps suggest git bisect? (sorry)
On the off chance - do you have this revert in your kernel?
commit 6a7b9f002eca6788d346c16a6ff0c218b41f8d1d
Author: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Date: Wed Jan 26 14:33:58 2022 +0100
Revert "tty: serial: Use fifo in 8250 console driver"
This reverts commit 5021d709b31b8a14317998a33cbc78be0de9ab30.
The patch is still a bit buggy, and this breaks some other hardware
types. It needs to be resubmitted in a non-buggy way, and make sure the
other hardware types also continue to work properly.