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From:   Thomas Gleixner <tglx@linutronix.de>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     LKML <linux-kernel@vger.kernel.org>, x86@kernel.org
Subject: Re: [patch 2/5] x86/idt: Add comments about early #PF handling
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Date:   Thu, 28 May 2020 20:44:06 +0200
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Peter Zijlstra <peterz@infradead.org> writes:
> On Thu, May 28, 2020 at 04:53:17PM +0200, Thomas Gleixner wrote:
>> The difference between 32 and 64 bit vs. early #PF handling is not
>> documented. Replace the FIXME at idt_setup_early_pf() with proper comments.
>> + * Note, that X86_64 cannot install the real #PF handler in
>> + * idt_setup_early_traps() because the memory intialization needs the #PF
>> + * handler from the early_idt_handler_array to initialize the early page
>> + * tables.
>
> + "See early_make_pgtables()" ?
>
> I had to frob around in head_64.S to find wth that early handler
> actually did.

True.