Recently due to commit 74af1456dfa0, the virtio device emulation
in KVMTOOL now calls irq__update_msix_route() upon guest poweroff
which results in KVMTOOL crash when Guest uses PLIC emulation in
user space. This is because irq__update_msix_route() expects the
irq_routing table to be available but the KVMTOOL PLIC emulation
does not populate any irq_routing entries.
Fixes: 74af1456dfa0 ("virtio: Cancel and join threads when exiting devices devices")
Signed-off-by: Anup Patel <apatel@xxxxxxxxxxxxxxxx>
---
riscv/plic.c | 32 ++++++++++++++++++++++++++++++++
1 file changed, 32 insertions(+)
diff --git a/riscv/plic.c b/riscv/plic.c
index ab7c574..6bd13ac 100644
--- a/riscv/plic.c
+++ b/riscv/plic.c
@@ -95,6 +95,8 @@
#define REG_SIZE 0x1000000
+#define IRQCHIP_PLIC_NR 0
+
struct plic_state;
struct plic_context {
@@ -500,6 +502,33 @@ static void plic__generate_fdt_node(void *fdt, struct kvm *kvm)
free(irq_cells);
}
+static int plic__irq_routing_init(struct kvm *kvm)
+{
+ int r;
+
+ /*
+ * This describes the default routing that the kernel uses without
+ * any routing explicitly set up via KVM_SET_GSI_ROUTING. So we
+ * don't need to commit these setting right now. The first actual
+ * user (MSI routing) will engage these mappings then.
+ */
+ for (next_gsi = 0; next_gsi < MAX_DEVICES; next_gsi++) {
+ r = irq__allocate_routing_entry();
+ if (r)
+ return r;
+
+ irq_routing->entries[irq_routing->nr++] =
+ (struct kvm_irq_routing_entry) {
+ .gsi = next_gsi,
+ .type = KVM_IRQ_ROUTING_IRQCHIP,
+ .u.irqchip.irqchip = IRQCHIP_PLIC_NR,
+ .u.irqchip.pin = next_gsi,
+ };
+ }
+
+ return 0;
+}
+
static int plic__init(struct kvm *kvm)
{
u32 i;
@@ -535,6 +564,9 @@ static int plic__init(struct kvm *kvm)
if (ret)
return ret;
+ /* Setup default IRQ routing */
+ plic__irq_routing_init(kvm);
+
plic.ready = true;
return 0;
--
2.34.1
