Re: [PATCH 0/2] KVM guest-kernel panics double fault

[Jan Kiszka <jan.kiszka@siemens.com>]

On 2012-01-12 16:43, Stephan Bärwolf wrote:
> From d62ca9897e9970d777aec1d399318b0df44489bd Mon Sep 17 00:00:00 2001
> From: Stephan Baerwolf <stephan.baerwolf@tu-ilmenau.de>
> Date: Thu, 12 Jan 2012 16:32:46 +0100
> Subject: [PATCH 0/2] KVM guest-kernel panics double fault
> 
> regarding: https://lkml.org/lkml/2011/12/28/170
> 
> On tested computers (Intel Core i5-2520M, Intel Xeon X5560
> and AMD Opteron 6174 [plus some misc.]), 32bit kvm guests
> (tested with winxp and linux-3.1) crash during execute of
> "syscall" (opcode 0f05). (double fault due to zeroed call
> of empty STAR-registers?)
> 
> 64bit Intel guests behave in 32bit protected compat like
> AMD and not like Intel. (which would have to #UD ...)
> 
> While the crash is bad (esp. for admins using VMs to isolate),
> because every unpriv. user can execute 0f05 - the misbehaviour
> with GenuineIntel-cpuid is just a blemish.
> 
> Best regards,
>     Stephan Bärwolf
> 
> 
> Stephan Baerwolf (2):
>   KVM: extend "struct x86_emulate_ops" with "get_cpuid"
>   KVM: fix missing "illegal instruction"-trap in protected modes
> 
>  arch/x86/include/asm/kvm_emulate.h |   19 ++++++++
>  arch/x86/kvm/emulate.c             |   80
> ++++++++++++++++++++++++++++++++++-
>  arch/x86/kvm/x86.c                 |   21 +++++++++
>  3 files changed, 117 insertions(+), 3 deletions(-)
> 

linux/scripts/checkpatch.pl can help identifying remaining style violations.

Moreover, when sending your patches via Thunderbird, you first need to
make sure that you have its line wrapping under control. "Toggle Word
Wrap" helps me for single patches. But for series, I prefer (scripted)
git format-patch/send-email.

Jan

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