This patch series implement everything that is needed to use AMD's AVIC while a nested guest is running including ability of the nested guest to use it, and brings feature parity vs APICv. I already posted patch 2, and patch 1 is extracted from another patch I posted today ‘KVM: x86: nSVM: implement nested VMLOAD/VMSAVE’ To make this series not depend on anything. This is RFC. There still corner cases that need to be fixed in regard to locking, especially around RCU use, locking is IMHO a bit ugly and inefficient. I did test this with nested guests (even 3 level of nesting, all with AVIC enabled), I also did a light test with VFIO passthrough. Suggestions, comments are welcome. Best regards, Maxim Levitsky Maxim Levitsky (11): KVM: x86: SVM: move nested_npt_enabled to svm.h KVM: x86: SVM: allow AVIC to co-exist with a nested guest running KVM: x86: mmu: allow to enable write tracking externally x86: KVMGT: use kvm_page_track_write_tracking_enable KVM: x86: mmu: add gfn_in_memslot helper KVM: x86: lapic: don't allow to change APIC ID when apic acceleration is enabled KVM: x86: SVM: remove avic's broken code that updated APIC ID KVM: x86: SVM: move avic state to separate struct KVM: x86: rename .set_apic_access_page_addr to reload_apic_access_page KVM: nSVM: implement support for nested AVIC KVM: SVM: allow to avoid not needed updates to is_running arch/x86/include/asm/kvm-x86-ops.h | 3 +- arch/x86/include/asm/kvm_host.h | 12 +- arch/x86/include/asm/kvm_page_track.h | 1 + arch/x86/include/asm/svm.h | 8 +- arch/x86/kvm/Kconfig | 3 - arch/x86/kvm/lapic.c | 28 +- arch/x86/kvm/mmu.h | 8 +- arch/x86/kvm/mmu/mmu.c | 16 +- arch/x86/kvm/mmu/page_track.c | 10 +- arch/x86/kvm/svm/avic.c | 763 +++++++++++++++++++++++--- arch/x86/kvm/svm/nested.c | 147 ++++- arch/x86/kvm/svm/svm.c | 61 +- arch/x86/kvm/svm/svm.h | 158 +++++- arch/x86/kvm/trace.h | 164 +++++- arch/x86/kvm/vmx/vmx.c | 8 +- arch/x86/kvm/x86.c | 31 +- drivers/gpu/drm/i915/Kconfig | 1 - drivers/gpu/drm/i915/gvt/kvmgt.c | 5 + include/linux/kvm_host.h | 10 +- virt/kvm/kvm_main.c | 3 +- 20 files changed, 1298 insertions(+), 142 deletions(-) -- 2.26.3