Re: [PATCH v2] x86, vt-d: enable x2apic opt out

[Woodhouse, David]

On Thu, 2011-04-14 at 08:06 +0100, Song, Youquan wrote:
> +               pr_info("Not enabling x2apic, firmware requests OS opt-out "
> +                         "x2apic.\n"); 

This output is far too innocuous. At the very least, it should have a
clear statement that this should leave you vulnerable to IRQ injection
attacks that intr-remapping + x2apic would have protected against.

It should probably look more like:

 WARN (1, "Your BIOS is broken and requested that x2apic be disabled\n"
    "This will leave your machine vulnerable to irq-injection attacks\n"
    "Use 'intel_iommu=no_x2apic_optout' to override BIOS request\n");


-- 
David Woodhouse                            Open Source Technology Centre
David.Woodhouse@xxxxxxxxx                              Intel Corporation

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