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Subject: Re: [tip:x86/mm] x86/boot/32: Defer resyncing initial_page_table
 until per-cpu is set up
To: Andy Shevchenko <andy.shevchenko@gmail.com>
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From: Jan Kiszka <jan.kiszka@siemens.com>
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Date: Mon, 8 May 2017 17:24:58 +0200
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On 2017-05-08 16:45, Andy Shevchenko wrote:
> On Mon, May 8, 2017 at 3:34 PM, Jan Kiszka <jan.kiszka@siemens.com> wrote:
>> On 2017-05-08 13:21, Andy Lutomirski wrote:
> 
>> Yes, it's an EFI thing. Unfortunately, I didn't make
>> earlycon/earlyprintk work yet.
> 
> Quark does use HS UART for the console and we have no support for such
> in x86/earlyprintk. earlycon should work if you add proper parameters
> to the command line (including port base address, no ttySx), though I
> don't remember if it makes really "early".

Ah, that explains it. I've tried earlycon, also with the apparently
correct params, but it didn't print anything in this case. And
earlyprintk=efi seems to use a framebuffer, while our devices are
headless...

Jan

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