From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marc Zyngier <marc.zyngier@arm.com>
Subject: Re: KVM on ARM crashes with new VGIC v4.7-rc7
Date: Mon, 25 Jul 2016 16:07:20 +0100
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To: Andrew Jones <drjones@redhat.com>
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On 25/07/16 15:28, Andrew Jones wrote:
> On Mon, Jul 25, 2016 at 03:05:46PM +0100, Marc Zyngier wrote:
>> News flash: Mark Rutland just saw it crashing on his Seattle using my
>> kernel that doesn't crash on mine. So we're looking at external factors
>> now. DT, firmware, whatever.
> 
> Interesting, especially with the information that the bug is also
> on v7 with uboot (where it's present with 4k pages), and on v8
> with UEFI (where it's not present with 4k pages, only 64k)

Here's what I get with Mark's DT:

[    2.199618] kvm [1]: 8-bit VMID
[    2.202756] kvm [1]: Hyp mode initialized successfully
[    2.207907] kvm [1]: GICV size 0x2000 not a multiple of page size 0x10000
[    2.214736] kvm [1]: virtual timer IRQ4

Somehow, we fail to detect that we cannot run with 64k pages,
because we cannot safely pass the 8kB region to the guest.
KVM should fail to initialize, or at least report that there
is no VGIC. Drew, is that what you have on your system as well?

That doesn't explain Stefan's issue though.

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny...