irqchip/gic-v4: Always configure affinity on VPE activation

There are currently two paths to set the initial affinity of a VPE:

 - at activation time on GICv4 without the stupid VMOVP list, and
   on GICv4.1

 - at map time for GICv4 with VMOVP list

The latter location may end-up modifying the affinity of VPE that is
currently running, making the results unpredictible.

Instead, unify the two paths, making sure to set the initial affinity only
at activation time.

Reported-by: Nianyao Tang <tangnianyao@huawei.com>
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/20240705093155.871070-2-maz@kernel.org

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index af5297ef22930f79abb1c4a199e6683691c716bc..387ac5a31d1ddb8c0326be8a964e5073df6f8ec4 100644 (file)
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -1809,13 +1809,9 @@ 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];
-                       struct irq_data *d = irq_get_irq_data(vpe->irq);
 
-                       /* Map the VPE to the first possible CPU */
-                       vpe->col_idx = cpumask_first(cpu_online_mask);
                        its_send_vmapp(its, vpe, true);
                        its_send_vinvall(its, vpe);
-                       irq_data_update_effective_affinity(d, cpumask_of(vpe->col_idx));
                }
        }
 
@@ -4582,6 +4578,10 @@ static int its_vpe_irq_domain_activate(struct irq_domain *domain,
        struct its_vpe *vpe = irq_data_get_irq_chip_data(d);
        struct its_node *its;
 
+       /* Map the VPE to the first possible CPU */
+       vpe->col_idx = cpumask_first(cpu_online_mask);
+       irq_data_update_effective_affinity(d, cpumask_of(vpe->col_idx));
+
        /*
         * If we use the list map, we issue VMAPP on demand... Unless
         * we're on a GICv4.1 and we eagerly map the VPE on all ITSs
@@ -4590,9 +4590,6 @@ static int its_vpe_irq_domain_activate(struct irq_domain *domain,
        if (!gic_requires_eager_mapping())
                return 0;
 
-       /* Map the VPE to the first possible CPU */
-       vpe->col_idx = cpumask_first(cpu_online_mask);
-
        list_for_each_entry(its, &its_nodes, entry) {
                if (!is_v4(its))
                        continue;
@@ -4601,8 +4598,6 @@ static int its_vpe_irq_domain_activate(struct irq_domain *domain,
                its_send_vinvall(its, vpe);
        }
 
-       irq_data_update_effective_affinity(d, cpumask_of(vpe->col_idx));
-
        return 0;
 }