[PATCH 3/3] irqchip/gic-v4: Make sure a VPE is locked when VMAPP is issued

[Marc Zyngier]

In order to make sure that vpe->col_idx is correctly sampled
when a VMAPP command is issued, we must hold the lock 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 locking
order.

Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
---
 drivers/irqchip/irq-gic-v3-its.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index b52d60097cad5..951ec140bcea2 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/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);
+		}
 	}
 }
 
-- 
2.39.2