From: Kunkun Jiang <jiangkunkun@xxxxxxxxxx>
vgic_its_save_device_tables will traverse its->device_list to
save DTE for each device. vgic_its_restore_device_tables will
traverse each entry of device table and check if it is valid.
Restore if valid.
But when MAPD unmaps a device, it does not invalidate the
corresponding DTE. In the scenario of continuous saves
and restores, there may be a situation where a device's DTE
is not saved but is restored. This is unreasonable and may
cause restore to fail. This patch clears the corresponding
DTE when MAPD unmaps a device.
Co-developed-by: Shusen Li <lishusen2@xxxxxxxxxx>
Signed-off-by: Shusen Li <lishusen2@xxxxxxxxxx>
Signed-off-by: Kunkun Jiang <jiangkunkun@xxxxxxxxxx>
Signed-off-by: Jing Zhang <jingzhangos@xxxxxxxxxx>
---
arch/arm64/kvm/vgic/vgic-its.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/kvm/vgic/vgic-its.c b/arch/arm64/kvm/vgic/vgic-its.c
index 2381bc5ce544..7c57c7c6fbff 100644
--- a/arch/arm64/kvm/vgic/vgic-its.c
+++ b/arch/arm64/kvm/vgic/vgic-its.c
@@ -1140,8 +1140,9 @@ static int vgic_its_cmd_handle_mapd(struct kvm *kvm, struct vgic_its *its,
u8 num_eventid_bits = its_cmd_get_size(its_cmd);
gpa_t itt_addr = its_cmd_get_ittaddr(its_cmd);
struct its_device *device;
+ gpa_t gpa;
- if (!vgic_its_check_id(its, its->baser_device_table, device_id, NULL))
+ if (!vgic_its_check_id(its, its->baser_device_table, device_id, &gpa))
return E_ITS_MAPD_DEVICE_OOR;
if (valid && num_eventid_bits > VITS_TYPER_IDBITS)
@@ -1161,8 +1162,17 @@ static int vgic_its_cmd_handle_mapd(struct kvm *kvm, struct vgic_its *its,
* The spec does not say whether unmapping a not-mapped device
* is an error, so we are done in any case.
*/
- if (!valid)
+ if (!valid) {
+ struct kvm *kvm = its->dev->kvm;
+ int dte_esz = vgic_its_get_abi(its)->dte_esz;
+ u64 val = 0;
+
+ if (KVM_BUG_ON(dte_esz != sizeof(val), kvm))
+ return -EINVAL;
+
+ vgic_write_guest_lock(kvm, gpa, &val, dte_esz);
return 0;
+ }
device = vgic_its_alloc_device(its, device_id, itt_addr,
num_eventid_bits);
--
2.47.0.277.g8800431eea-goog
