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Date: Fri, 28 Oct 2016 21:00:05 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Michal Necasek <michal.necasek@oracle.com>
cc: prarit@redhat.com, ville.syrjala@linux.intel.com,
        michael.thayer@oracle.com, knut.osmundsen@oracle.com,
        frank.mehnert@oracle.com, linux-kernel@vger.kernel.org
Subject: Re: 4.8.2 not booting in 32-bit VM without I/O-APIC
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On Fri, 28 Oct 2016, Michal Necasek wrote:
> 
>  Sorry if I wasn't clear. No, it doesn't work for us. The ff8560512b8d
> commit fixes the APIC poking on machines where there is no local APIC
> available (and thus fixes the committer's machine), but it doesn't work
> in our case, where there is a local APIC but no I/O APIC, no ACPI MADT,
> and no MP tables.

> In other words, for us boot_cpu_has(X86_FEATURE_APIC) is true but the
> APIC has not been set up yet because init_apic_mappings() hasn't been
> run.

Gah. Sorry, misunderstood you. Lemme stare in the code.

Thanks,

	tglx