[PATCH 0/6] KVM: x86: Make the cause of instruction emulation available to user-space

From: David Edmondson
Date: Mon Apr 12 2021 - 09:09:50 EST


Instruction emulation happens for a variety of reasons, yet on error
we have no idea exactly what triggered it. Add a cause of emulation to
the various originators and pass it upstream when emulation fails.

Joao originally produced the patches but is busy with other things and
I wanted to use it, so picked it up.

Tested by reverting commit 51b958e5aeb1e18c00332e0b37c5d4e95a3eff84
("KVM: x86: clflushopt should be treated as a no-op by emulation")
then running the test included in
https://lore.kernel.org/r/20201118121129.6276-1-david.edmondson@xxxxxxxxxx.

Joao Martins (6):
KVM: x86: add an emulation_reason to x86_emulate_instruction()
KVM: x86: pass emulation_reason to handle_emulation_failure()
KVM: x86: add emulation_reason to kvm_emulate_instruction()
KVM: x86: pass a proper reason to kvm_emulate_instruction()
KVM: SVM: pass a proper reason in kvm_emulate_instruction()
KVM: VMX: pass a proper reason in kvm_emulate_instruction()

arch/x86/include/asm/kvm_host.h | 27 +++++++++++++++++++++++--
arch/x86/kvm/mmu/mmu.c | 4 ++--
arch/x86/kvm/svm/avic.c | 3 ++-
arch/x86/kvm/svm/svm.c | 26 +++++++++++++-----------
arch/x86/kvm/vmx/vmx.c | 17 ++++++++--------
arch/x86/kvm/x86.c | 35 ++++++++++++++++++++++-----------
arch/x86/kvm/x86.h | 3 ++-
7 files changed, 78 insertions(+), 37 deletions(-)

--
2.30.2