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;
}
