Am 03.03.2017 um 17:55 schrieb Russell King - ARM Linux:

On Fri, Mar 03, 2017 at 05:42:02PM +0100, Marc Gonzalez wrote:

quoted

I'm confused about early consoles and earlyprintk, and all that good stuff.
When my kernel panics, I don't get the expected output.

Using "mem=256M ignore_loglevel earlyprintk"

[...]

quoted

[    0.014325] Console: colour dummy device 80x30
[    0.018885] console [tty0] enabled
[    0.022396] bootconsole [earlycon0] disabled

And it hangs there.

tty0 is the kernel virtual terminal console, which is what appears on
VGA or framebuffers.  This is the default console if nothing else is
specified.

What happened here is that the virtual terminal console registered, was
detected to be the system console, so early console was shut down, and
the boot messages logged to the virtual terminal console instead.

Why does passing console= make a difference though?

I expect stdout-path to have the same effect as the command line, and I
am pretty sure that that was previous behavior in, e.g., v4.4.

Note that I am using earlycon, as opposed to earlyprintk above.

Regards,
Andreas

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