On 2024/8/6 20:39, Zenghui Yu wrote:
On 2024/8/6 17:23, Zenghui Yu wrote:
> The following diff seems work for me.
>
> diff --git a/arch/arm64/kvm/vgic/vgic-debug.c
> b/arch/arm64/kvm/vgic/vgic-debug.c
> index 6faa1d16c9ce..f56f74c8cf54 100644
> --- a/arch/arm64/kvm/vgic/vgic-debug.c
> +++ b/arch/arm64/kvm/vgic/vgic-debug.c
> @@ -41,11 +41,16 @@ static void iter_next(struct kvm *kvm, struct vgic_state_iter *iter)
> return;
> }
>
> + iter->intid++;
[*]
> + if (iter->intid == VGIC_NR_PRIVATE_IRQS &&
> + ++iter->vcpu_id < iter->nr_cpus)
> + iter->intid = 0;
> +
> /*
> * Let the xarray drive the iterator after the last SPI, as the iterator
> * has exhausted the sequentially-allocated INTID space.
> */
> - if (iter->intid >= (iter->nr_spis + VGIC_NR_PRIVATE_IRQS - 1)) {
> + if (iter->intid >= (iter->nr_spis + VGIC_NR_PRIVATE_IRQS)) {
> if (iter->lpi_idx < iter->nr_lpis)
> xa_find_after(&dist->lpi_xa, &iter->intid,
Just noticed that it's wrong to increase intid before xa_find_after(),
which would break the LPI case. Let me have a think...
So searching the LPI xarray and populating lpi_idx when the guest
doesn't have LPI is pointless. We can fix the reported issue by dealing
with the 'nr_lpis == 0' case directly, which might be the easiest
approach. Let me know what do you think.
diff --git a/arch/arm64/kvm/vgic/vgic-debug.c
b/arch/arm64/kvm/vgic/vgic-debug.c
index bcbc8c986b1d..8177e5972ea8 100644
--- a/arch/arm64/kvm/vgic/vgic-debug.c
+++ b/arch/arm64/kvm/vgic/vgic-debug.c
@@ -45,7 +45,8 @@ static void iter_next(struct kvm *kvm, struct
vgic_state_iter *iter)
* Let the xarray drive the iterator after the last SPI, as the iterator
* has exhausted the sequentially-allocated INTID space.
*/
- if (iter->intid >= (iter->nr_spis + VGIC_NR_PRIVATE_IRQS - 1)) {
+ if (iter->intid >= (iter->nr_spis + VGIC_NR_PRIVATE_IRQS - 1) &&
+ iter->nr_lpis) {
if (iter->lpi_idx < iter->nr_lpis)
xa_find_after(&dist->lpi_xa, &iter->intid,
VGIC_LPI_MAX_INTID,
@@ -112,7 +113,7 @@ static bool end_of_vgic(struct vgic_state_iter *iter)
return iter->dist_id > 0 &&
iter->vcpu_id == iter->nr_cpus &&
iter->intid >= (iter->nr_spis + VGIC_NR_PRIVATE_IRQS) &&
- iter->lpi_idx > iter->nr_lpis;
+ (iter->lpi_idx > iter->nr_lpis || !iter->nr_lpis);
}
static void *vgic_debug_start(struct seq_file *s, loff_t *pos)
Thanks,
Zenghui
