irqchip/gic-v4: Make sure a VPE is locked when VMAPP is issued

In order to make sure that vpe->col_idx is correctly sampled when a VMAPP
command is issued, the vpe_lock must be held for the VPE. This is now
possible since the introduction of the per-VM vmapp_lock, which can be
taken before vpe_lock in the correct locking order.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Nianyao Tang <tangnianyao@huawei.com>
Link: https://lore.kernel.org/r/20240705093155.871070-4-maz@kernel.org

drivers/irqchip/irq-gic-v3-its.c

@@ -1810,7 +1810,9 @@ static void its_map_vm(struct its_node *its, struct its_vm *vm)
 		for (i = 0; i < vm->nr_vpes; i++) {
 			struct its_vpe *vpe = vm->vpes[i];
 
-			its_send_vmapp(its, vpe, true);
+			scoped_guard(raw_spinlock, &vpe->vpe_lock)
+				its_send_vmapp(its, vpe, true);
+
 			its_send_vinvall(its, vpe);
 		}
 	}
@@ -1827,8 +1829,10 @@ static void its_unmap_vm(struct its_node *its, struct its_vm *vm)
 	if (!--vm->vlpi_count[its->list_nr]) {
 		int i;
 
-		for (i = 0; i < vm->nr_vpes; i++)
+		for (i = 0; i < vm->nr_vpes; i++) {
+			guard(raw_spinlock)(&vm->vpes[i]->vpe_lock);
 			its_send_vmapp(its, vm->vpes[i], false);
+		}
 	}
 }