From: Paolo Bonzini <pbonzini@redhat.com>
To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Subject: [RFC PATCH 0/4] KVM: Emulate UMIP (or almost do so)
Date: Tue, 12 Jul 2016 21:20:19 +0200 [thread overview]
Message-ID: <1468351223-3250-1-git-send-email-pbonzini@redhat.com> (raw)
UMIP (User-Mode Instruction Prevention) is a feature of future
Intel processors (Cannonlake?) that blocks SLDT, SGDT, STR, SIDT
and SMSW from user-mode processes.
The idea here is to use virtualization intercepts to emulate UMIP; it
slows down the instructions when they're executed in ring 0, but they
are really never executed in practice. On AMD systems it's possible
to emulate it entirely; instead on Intel systems it's *almost* possible
to emulate it, because SMSW doesn't cause a vmexit, and hence SMSW will
not fault.
This patch series provides the infrastructure and implements it on
Intel. I tested it through kvm-unit-tests.
Still I think the idea is interesting, even if it's buggy for current
Intel processors. Any opinions?
Paolo
Paolo Bonzini (4):
x86: add UMIP feature and CR4 bit
KVM: x86: emulate sldt and str
KVM: x86: add support for emulating UMIP
KVM: vmx: add support for emulating UMIP
arch/x86/include/asm/cpufeatures.h | 1 +
arch/x86/include/asm/kvm_host.h | 3 ++-
arch/x86/include/asm/vmx.h | 1 +
arch/x86/include/uapi/asm/processor-flags.h | 2 ++
arch/x86/include/uapi/asm/vmx.h | 4 +++
arch/x86/kvm/cpuid.c | 5 +++-
arch/x86/kvm/cpuid.h | 8 ++++++
arch/x86/kvm/emulate.c | 40 ++++++++++++++++++++++++-----
arch/x86/kvm/svm.c | 6 +++++
arch/x86/kvm/vmx.c | 40 ++++++++++++++++++++++++++++-
arch/x86/kvm/x86.c | 3 +++
11 files changed, 104 insertions(+), 9 deletions(-)
--
1.8.3.1
next reply other threads:[~2016-07-12 19:20 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-07-12 19:20 Paolo Bonzini [this message]
2016-07-12 19:20 ` [RFC PATCH 1/4] x86: add UMIP feature and CR4 bit Paolo Bonzini
2016-07-12 19:20 ` [RFC PATCH 2/4] KVM: x86: emulate sldt and str Paolo Bonzini
2016-07-12 19:20 ` [RFC PATCH 3/4] KVM: x86: add support for emulating UMIP Paolo Bonzini
2016-07-13 20:03 ` Radim Krčmář
2016-07-14 7:00 ` Paolo Bonzini
2016-07-14 12:24 ` Radim Krčmář
2016-07-12 19:20 ` [RFC PATCH 4/4] KVM: vmx: " Paolo Bonzini
2016-07-13 9:21 ` Yang Zhang
2016-07-13 9:35 ` Paolo Bonzini
2016-07-13 9:54 ` Yang Zhang
2016-07-13 9:35 ` Paolo Bonzini
2016-07-13 10:02 ` Yang Zhang
2016-07-13 10:21 ` Paolo Bonzini
2016-07-13 20:30 ` Radim Krčmář
2016-07-14 8:09 ` Paolo Bonzini
2016-07-14 12:36 ` Radim Krčmář
2016-07-14 12:54 ` Paolo Bonzini
2016-07-31 2:32 ` Wanpeng Li
2016-08-01 15:01 ` Paolo Bonzini
2016-08-02 1:05 ` Wanpeng Li
2016-07-13 8:29 ` [RFC PATCH 0/4] KVM: Emulate UMIP (or almost do so) Yang Zhang
2016-07-13 9:34 ` Paolo Bonzini
2016-12-13 4:03 ` Li, Liang Z
2016-12-13 11:03 ` Paolo Bonzini
2017-03-01 9:04 ` Yu Zhang
2017-03-06 21:07 ` Paolo Bonzini
2017-03-10 8:02 ` Yu Zhang
2017-03-10 8:36 ` Paolo Bonzini
2017-03-10 9:31 ` Yu Zhang
2017-03-10 11:28 ` Yu Zhang
2017-03-10 15:00 ` Paolo Bonzini
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