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KVM: x86: Fix uninitialized eoi_exit_bitmap usage in vcpu_load_eoi_exitmap()

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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 <vkuznets@redhat.com>
Signed-off-by: Huang Le <huangle1@jd.com>
Message-Id: <62115b277dab49ea97da5633f8522daf@jd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
黄乐 2021-11-15 14:08:29 +00:00 committed by Greg Kroah-Hartman
parent 5969e2435c
commit c3168ef1f1
1 changed files with 6 additions and 2 deletions
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8
arch/x86/kvm/x86.c
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@ -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,