From: Don Zickus <dzickus@redhat.com>
To: Andy Lutomirski <luto@amacapital.net>
Cc: Gleb Natapov <gleb@redhat.com>,
Alex Williamson <alex.williamson@redhat.com>,
x86@kernel.org, LKML <linux-kernel@vger.kernel.org>,
Suresh Siddha <suresh.b.siddha@intel.com>,
"H. Peter Anvin" <hpa@zytor.com>,
Prarit Bhargava <prarit@redhat.com>
Subject: Re: [PATCH] intel_irq_remapping: Clean up x2apic optout security warning mess
Date: Mon, 4 Feb 2013 13:20:15 -0500 [thread overview]
Message-ID: <20130204182015.GY98867@redhat.com> (raw)
In-Reply-To: <2011b943a886fd7c46079eb10bc24fc130587503.1359759303.git.luto@amacapital.net>
On Fri, Feb 01, 2013 at 02:57:43PM -0800, Andy Lutomirski wrote:
> Current kernels print this on my Dell server:
>
> ------------[ cut here ]------------
> WARNING: at drivers/iommu/intel_irq_remapping.c:542
> intel_enable_irq_remapping+0x7b/0x27e()
> Hardware name: PowerEdge R620
> Your BIOS is broken and requested that x2apic be disabled
> This will leave your machine vulnerable to irq-injection attacks
> Use 'intremap=no_x2apic_optout' to override BIOS request
> [...]
> Enabled IRQ remapping in xapic mode
> x2apic not enabled, IRQ remapping is in xapic mode
>
> This is inconsistent with itself -- interrupt remapping is *on*.
>
> Fix the mess by making the warnings say what they mean and my making
> sure that compatibility format interrupts (the dangerous ones) are
> disabled if x2apic is present regardless of BIOS settings.
Yeah, this fixes the problem on our end too. Thank Andy!
Cheers,
Don
next prev parent reply other threads:[~2013-02-04 18:20 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-01-31 16:40 [PATCH] x86, x2apic: Only WARN on broken BIOSes inside a virtual guest Don Zickus
2013-01-31 18:52 ` Gleb Natapov
2013-01-31 19:34 ` Don Zickus
2013-01-31 20:00 ` Gleb Natapov
2013-01-31 20:52 ` Alex Williamson
2013-02-01 22:00 ` Andy Lutomirski
2013-02-01 22:57 ` [PATCH] intel_irq_remapping: Clean up x2apic optout security warning mess Andy Lutomirski
2013-02-03 19:29 ` [tip:x86/apic] x86/intel/irq_remapping: Clean up x2apic opt-out " tip-bot for Andy Lutomirski
2013-02-04 18:20 ` Don Zickus [this message]
2013-02-04 19:04 ` [PATCH] intel_irq_remapping: Clean up x2apic optout " Alex Williamson
2013-02-04 19:19 ` Andy Lutomirski
2013-02-04 19:39 ` Alex Williamson
2013-02-04 19:47 ` Andy Lutomirski
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