Yes, these can happen. The issue is that benign exceptions are delivered serially, but two of them (#DB and #AC) can also happen during exception delivery itself. The subsequent infinite stream of exceptions causes the processor to never exit guest mode.
Paolo Eric Northup (1): KVM: x86: work around infinite loop in microcode when #AC is delivered Paolo Bonzini (2): KVM: svm: unconditionally intercept #DB KVM: x86: rename update_db_bp_intercept to update_bp_intercept arch/x86/include/asm/kvm_host.h | 2 +- arch/x86/include/uapi/asm/svm.h | 1 + arch/x86/kvm/svm.c | 22 +++++++++++----------- arch/x86/kvm/vmx.c | 7 +++++-- arch/x86/kvm/x86.c | 2 +- 5 files changed, 19 insertions(+), 15 deletions(-) -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
