This is a note to let you know that I've just added the patch titled platform: finally disallow IRQ0 in platform_get_irq() and its ilk to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: platform-finally-disallow-irq0-in-platform_get_irq-a.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit f774747a385caf5dca7e9c779ba82873c11159a8 Author: Sergey Shtylyov <s.shtylyov@xxxxxx> Date: Fri Mar 11 22:35:29 2022 +0300 platform: finally disallow IRQ0 in platform_get_irq() and its ilk [ Upstream commit ce753ad1549cbe9ccaea4c06a1f5fa47432c8289 ] The commit a85a6c86c25b ("driver core: platform: Clarify that IRQ 0 is invalid") only calls WARN() when IRQ0 is about to be returned, however using IRQ0 is considered invalid (according to Linus) outside the arch/ code where it's used by the i8253 drivers. Many driver subsystems treat 0 specially (e.g. as an indication of the polling mode by libata), so the users of platform_get_irq[_byname]() in them would have to filter out IRQ0 explicitly and this (quite obviously) doesn't scale... Let's finally get this straight and return -EINVAL instead of IRQ0! Fixes: a85a6c86c25b ("driver core: platform: Clarify that IRQ 0 is invalid") Acked-by: Marc Zyngier <maz@xxxxxxxxxx> Signed-off-by: Sergey Shtylyov <s.shtylyov@xxxxxx> Link: https://lore.kernel.org/r/025679e1-1f0a-ae4b-4369-01164f691511@xxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/base/platform.c b/drivers/base/platform.c index 88aef93eb4dd..ad9ef67df7ad 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -235,7 +235,8 @@ int platform_get_irq_optional(struct platform_device *dev, unsigned int num) ret = -ENXIO; #endif out: - WARN(ret == 0, "0 is an invalid IRQ number\n"); + if (WARN(!ret, "0 is an invalid IRQ number\n")) + return -EINVAL; return ret; } EXPORT_SYMBOL_GPL(platform_get_irq_optional); @@ -328,7 +329,8 @@ static int __platform_get_irq_byname(struct platform_device *dev, r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name); if (r) { - WARN(r->start == 0, "0 is an invalid IRQ number\n"); + if (WARN(!r->start, "0 is an invalid IRQ number\n")) + return -EINVAL; return r->start; }