gpio: mxc: fix race between chained IRQ handler install and probe completion

mxc_update_irq_chained_handler() is called before the IRQ domain, the
generic IRQ chip, and the port list entry are set up. If an interrupt
arrives in that window:

 - mx3_gpio_irq_handler() calls generic_handle_domain_irq() with
   port->domain still NULL.
 - mx2_gpio_irq_handler() walks mxc_gpio_ports, but the port has not
   been added to the list yet.

Additionally, if any of the subsequent probe steps
(gpio_generic_chip_init(), devm_gpiochip_add_data(),
irq_domain_create_legacy(), or mxc_gpio_init_gc()) fail, the error
paths never unregister the chained handler, leaving a dangling handler
that points at freed memory.

Move the handler installation after all its dependencies are ready and
after list_add_tail(), so the handler is never live while the data
structures it touches are incomplete, and is never installed if probe
fails.

Fixes: 5f6d1998ad ("gpio: mxc: release the parent IRQ in runtime suspend")
Assisted-by: LLM
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Linus Walleij <linusw@kernel.org>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Link: https://patch.msgid.link/20261013-gpio-mxc-cleanup-v7-1-c4d769587d3e@nxp.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
This commit is contained in:
Peng Fan 2026-10-13 14:01:09 +08:00 • committed by Bartosz Golaszewski
commit 38d44f78f0