From cddb536a73ef2c82ce04059dc61c65e85a355561 Mon Sep 17 00:00:00 2001 From: Kefeng Wang Date: Fri, 5 May 2023 17:06:54 +0800 Subject: [PATCH] irqchip/mbigen: Unify the error handling in mbigen_of_create_domain() Dan Carpenter reported that commit fea087fc291b "irqchip/mbigen: move to use bus_get_dev_root()" leads to the following Smatch static checker warning: drivers/irqchip/irq-mbigen.c:258 mbigen_of_create_domain() error: potentially dereferencing uninitialized 'child'. It should not cause a problem on real hardware, but better to fix the warning, let's move the bus_get_dev_root() out of the loop, and unify the error handling to silence it. Reported-by: Dan Carpenter Signed-off-by: Kefeng Wang Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20230505090654.12793-1-wangkefeng.wang@huawei.com --- drivers/irqchip/irq-mbigen.c | 31 ++++++++++++++++++------------- 1 file changed, 18 insertions(+), 13 deletions(-) diff --git a/drivers/irqchip/irq-mbigen.c b/drivers/irqchip/irq-mbigen.c index eada5e0e3eb9..5101a3fb11df 100644 --- a/drivers/irqchip/irq-mbigen.c +++ b/drivers/irqchip/irq-mbigen.c @@ -240,26 +240,27 @@ static int mbigen_of_create_domain(struct platform_device *pdev, struct irq_domain *domain; struct device_node *np; u32 num_pins; + int ret = 0; + + parent = bus_get_dev_root(&platform_bus_type); + if (!parent) + return -ENODEV; for_each_child_of_node(pdev->dev.of_node, np) { if (!of_property_read_bool(np, "interrupt-controller")) continue; - parent = bus_get_dev_root(&platform_bus_type); - if (parent) { - child = of_platform_device_create(np, NULL, parent); - put_device(parent); - if (!child) { - of_node_put(np); - return -ENOMEM; - } + child = of_platform_device_create(np, NULL, parent); + if (!child) { + ret = -ENOMEM; + break; } if (of_property_read_u32(child->dev.of_node, "num-pins", &num_pins) < 0) { dev_err(&pdev->dev, "No num-pins property\n"); - of_node_put(np); - return -EINVAL; + ret = -EINVAL; + break; } domain = platform_msi_create_device_domain(&child->dev, num_pins, @@ -267,12 +268,16 @@ static int mbigen_of_create_domain(struct platform_device *pdev, &mbigen_domain_ops, mgn_chip); if (!domain) { - of_node_put(np); - return -ENOMEM; + ret = -ENOMEM; + break; } } - return 0; + put_device(parent); + if (ret) + of_node_put(np); + + return ret; } #ifdef CONFIG_ACPI -- 2.25.1