On 11/15/21 15:08, 黄乐 wrote:

In vcpu_load_eoi_exitmap(), currently the eoi_exit_bitmap[4] array is initialized only when Hyper-V context is available, in other path it is just passed to kvm_x86_ops.load_eoi_exitmap() directly from on the stack, which would cause unexpected interrupt delivery/handling issues, e.g. an *old* linux kernel that relies on PIT to do clock calibration on KVM might randomly fail to boot.

Fix it by passing ioapic_handled_vectors to load_eoi_exitmap() when Hyper-V context is not available.

Fixes: f2bc14b69c38 ("KVM: x86: hyper-v: Prepare to meet unallocated Hyper-V context") Cc: stable@vger.kernel.org Reviewed-by: Vitaly Kuznetsov vkuznets@redhat.com Signed-off-by: Huang Le huangle1@jd.com

---

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index dc7eb5fddfd3..26466f94e31a 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -9547,12 +9547,16 @@ static void vcpu_load_eoi_exitmap(struct kvm_vcpu *vcpu) if (!kvm_apic_hw_enabled(vcpu->arch.apic)) return;

• if (to_hv_vcpu(vcpu))

• if (to_hv_vcpu(vcpu)) { bitmap_or((ulong *)eoi_exit_bitmap, vcpu->arch.ioapic_handled_vectors, to_hv_synic(vcpu)->vec_bitmap, 256);

• static_call(kvm_x86_load_eoi_exitmap)(vcpu, eoi_exit_bitmap);
  

• return;
  

• }

• static_call(kvm_x86_load_eoi_exitmap)(vcpu, eoi_exit_bitmap);

• static_call(kvm_x86_load_eoi_exitmap)(

• vcpu, (u64 *)vcpu->arch.ioapic_handled_vectors);
  

  }

void kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm,

Queued, thanks.

Paolo