From: 黄乐 Date: Mon, 15 Nov 2021 14:08:29 +0000 (+0000) Subject: KVM: x86: Fix uninitialized eoi_exit_bitmap usage in vcpu_load_eoi_exitmap() X-Git-Tag: accepted/tizen/unified/20230118.172025~4915 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=c3168ef1f12d817759508b3efbefc467cf2c4cc6;p=platform%2Fkernel%2Flinux-rpi.git KVM: x86: Fix uninitialized eoi_exit_bitmap usage in vcpu_load_eoi_exitmap() commit c5adbb3af051079f35abfa26551107e2c653087f upstream. 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 Signed-off-by: Huang Le Message-Id: <62115b277dab49ea97da5633f8522daf@jd.com> Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 66e4e9a..16c7465 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -9429,12 +9429,16 @@ 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,