linux-stable/arch/x86/kvm
Yadong Qi bf0cd88ce3 KVM: x86: emulate wait-for-SIPI and SIPI-VMExit
Background: We have a lightweight HV, it needs INIT-VMExit and
SIPI-VMExit to wake-up APs for guests since it do not monitor
the Local APIC. But currently virtual wait-for-SIPI(WFS) state
is not supported in nVMX, so when running on top of KVM, the L1
HV cannot receive the INIT-VMExit and SIPI-VMExit which cause
the L2 guest cannot wake up the APs.

According to Intel SDM Chapter 25.2 Other Causes of VM Exits,
SIPIs cause VM exits when a logical processor is in
wait-for-SIPI state.

In this patch:
    1. introduce SIPI exit reason,
    2. introduce wait-for-SIPI state for nVMX,
    3. advertise wait-for-SIPI support to guest.

When L1 hypervisor is not monitoring Local APIC, L0 need to emulate
INIT-VMExit and SIPI-VMExit to L1 to emulate INIT-SIPI-SIPI for
L2. L2 LAPIC write would be traped by L0 Hypervisor(KVM), L0 should
emulate the INIT/SIPI vmexit to L1 hypervisor to set proper state
for L2's vcpu state.

Handle procdure:
Source vCPU:
    L2 write LAPIC.ICR(INIT).
    L0 trap LAPIC.ICR write(INIT): inject a latched INIT event to target
       vCPU.
Target vCPU:
    L0 emulate an INIT VMExit to L1 if is guest mode.
    L1 set guest VMCS, guest_activity_state=WAIT_SIPI, vmresume.
    L0 set vcpu.mp_state to INIT_RECEIVED if (vmcs12.guest_activity_state
       == WAIT_SIPI).

Source vCPU:
    L2 write LAPIC.ICR(SIPI).
    L0 trap LAPIC.ICR write(INIT): inject a latched SIPI event to traget
       vCPU.
Target vCPU:
    L0 emulate an SIPI VMExit to L1 if (vcpu.mp_state == INIT_RECEIVED).
    L1 set CS:IP, guest_activity_state=ACTIVE, vmresume.
    L0 resume to L2.
    L2 start-up.

Signed-off-by: Yadong Qi <yadong.qi@intel.com>
Message-Id: <20200922052343.84388-1-yadong.qi@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201106065122.403183-1-yadong.qi@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-11-15 09:49:09 -05:00
..
mmu kvm: mmu: fix is_tdp_mmu_check when the TDP MMU is not in use 2020-11-15 08:55:43 -05:00
svm KVM: x86: Return bool instead of int for CR4 and SREGS validity checks 2020-11-15 09:49:08 -05:00
vmx KVM: x86: emulate wait-for-SIPI and SIPI-VMExit 2020-11-15 09:49:09 -05:00
cpuid.c KVM: x86: Introduce cr3_lm_rsvd_bits in kvm_vcpu_arch 2020-11-13 06:28:37 -05:00
cpuid.h kvm: x86: ensure pv_cpuid.features is initialized when enabling cap 2020-11-08 04:41:29 -05:00
debugfs.c KVM: let kvm_destroy_vm_debugfs clean up vCPU debugfs directories 2020-06-04 11:00:54 -04:00
emulate.c KVM: x86: clflushopt should be treated as a no-op by emulation 2020-11-13 06:28:33 -05:00
hyperv.c ARM: 2020-10-23 11:17:56 -07:00
hyperv.h x86/kvm/hyper-v: Add support for synthetic debugger interface 2020-06-01 04:26:11 -04:00
i8254.c kvm: i8254: remove redundant assignment to pointer s 2020-06-11 12:35:18 -04:00
i8254.h
i8259.c
ioapic.c KVM: ioapic: break infinite recursion on lazy EOI 2020-10-24 04:42:06 -04:00
ioapic.h kvm/x86: Remove redundant function implementations 2020-05-27 13:11:10 -04:00
irq.c KVM: nSVM: extract svm_set_gif 2020-06-01 04:26:01 -04:00
irq.h kvm/x86: Remove redundant function implementations 2020-05-27 13:11:10 -04:00
irq_comm.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
Kconfig x86/kvm: hide KVM options from menuconfig when KVM is not compiled 2020-10-21 17:36:30 -04:00
kvm_cache_regs.h KVM: x86: Let the guest own CR4.FSGSBASE 2020-10-21 17:48:50 -04:00
kvm_emulate.h ARM: 2020-04-02 15:13:15 -07:00
lapic.c KVM: x86: fix apic_accept_events vs check_nested_events 2020-11-15 09:49:08 -05:00
lapic.h KVM: nVMX: Morph notification vector IRQ on nested VM-Enter to pending PI 2020-09-28 07:57:22 -04:00
Makefile kvm: x86/mmu: Init / Uninit the TDP MMU 2020-10-21 18:17:00 -04:00
mmu.h KVM: x86: Move illegal GPA helper out of the MMU code 2020-09-28 07:57:27 -04:00
mtrr.c
pmu.c KVM/x86: pmu: Fix #GP condition check for RDPMC emulation 2020-07-09 07:08:37 -04:00
pmu.h kvm: x86: limit the maximum number of vPMU fixed counters to 3 2020-07-08 16:21:59 -04:00
trace.h KVM: x86: Use common definition for kvm_nested_vmexit tracepoint 2020-09-28 07:57:52 -04:00
tss.h
x86.c KVM: x86: Return bool instead of int for CR4 and SREGS validity checks 2020-11-15 09:49:08 -05:00
x86.h KVM: x86: Return bool instead of int for CR4 and SREGS validity checks 2020-11-15 09:49:08 -05:00