Re: [PATCH v2] console: use first console if stdout-path device doesn't appear

From: Larry Finger
Date: Mon Oct 31 2016 - 11:59:14 EST


On 10/31/2016 07:14 AM, Paul Burton wrote:
If a device tree specified a preferred device for kernel console output
via the stdout-path or linux,stdout-path chosen node properties there's
no guarantee that it will have specified a device for which we have a
driver. It may also be the case that we do have a driver but it doesn't
call of_console_check() to register as a preferred console (eg. offb
driver as used on powermac systems). In these cases try to ensure that
we provide some console output by enabling the first usable registered
console, which we keep track of with the of_fallback_console variable.

Tested in QEMU with a PowerPC pseries_defconfig kernel.

The patch fails to fix my real PowerPC. I still get a kernel panic for an attempt to kill init. This first test was done with 4.9-rc2. I am in the process of updating to -rc3 to see if that changes anything. Later today when that build finishes, I will report those results.

Larry