From: Kunkun Jiang <jiangkunkun@xxxxxxxxxx> When DISCARD frees an ITE, it does not invalidate the corresponding ITE. In the scenario of continuous saves and restores, there may be a situation where an ITE is not saved but is restored. This is unreasonable and may cause restore to fail. This patch clears the corresponding ITE when DISCARD frees an ITE. Signed-off-by: Kunkun Jiang <jiangkunkun@xxxxxxxxxx> Signed-off-by: Jing Zhang <jingzhangos@xxxxxxxxxx> --- arch/arm64/kvm/vgic/vgic-its.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/arm64/kvm/vgic/vgic-its.c b/arch/arm64/kvm/vgic/vgic-its.c index 7c57c7c6fbff..df8408ceae30 100644 --- a/arch/arm64/kvm/vgic/vgic-its.c +++ b/arch/arm64/kvm/vgic/vgic-its.c @@ -782,6 +782,10 @@ static int vgic_its_cmd_handle_discard(struct kvm *kvm, struct vgic_its *its, ite = find_ite(its, device_id, event_id); if (ite && its_is_collection_mapped(ite->collection)) { + struct its_device *device = find_its_device(its, device_id); + int ite_esz = vgic_its_get_abi(its)->ite_esz; + gpa_t gpa = device->itt_addr + ite->event_id * ite_esz; + u64 val = 0; /* * Though the spec talks about removing the pending state, we * don't bother here since we clear the ITTE anyway and the @@ -790,6 +794,11 @@ static int vgic_its_cmd_handle_discard(struct kvm *kvm, struct vgic_its *its, vgic_its_invalidate_cache(its); its_free_ite(kvm, ite); + + if (KVM_BUG_ON(ite_esz != sizeof(val), kvm)) + return -EINVAL; + + vgic_write_guest_lock(kvm, gpa, &val, ite_esz); return 0; } -- 2.47.0.277.g8800431eea-goog