irqdomain: Drop bogus fwspec-mapping error handling

BugLink: https://bugs.launchpad.net/bugs/2011425
commit e3b7ab025e931accdc2c12acf9b75c6197f1c062 upstream.

In case a newly allocated IRQ ever ends up not having any associated
struct irq_data it would not even be possible to dispose the mapping.

Replace the bogus disposal with a WARN_ON().

This will also be used to fix a shared-interrupt mapping race, hence the
CC-stable tag.

Fixes: 1e2a7d78499e ("irqdomain: Don't set type when mapping an IRQ")
Cc: stable@vger.kernel.org      # 4.8
Tested-by: Hsin-Yi Wang <hsinyi@chromium.org>
Tested-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230213104302.17307-4-johan+linaro@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>

diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 1b5e9decd8543729d4cd97816cb1304e67f88bab..3d6a14efae6238b9960380b3633c4672a8291c4b 100644 (file)
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -853,13 +853,8 @@ unsigned int irq_create_fwspec_mapping(struct irq_fwspec *fwspec)
        }
 
        irq_data = irq_get_irq_data(virq);
-       if (!irq_data) {
-               if (irq_domain_is_hierarchy(domain))
-                       irq_domain_free_irqs(virq, 1);
-               else
-                       irq_dispose_mapping(virq);
+       if (WARN_ON(!irq_data))
                return 0;
-       }
 
        /* Store trigger type */
        irqd_set_trigger_type(irq_data, type);