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From: "Rob Herring (Arm)" <robh@kernel.org>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	"Rafael J. Wysocki" <rafael@kernel.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>, linux-kernel@vger.kernel.org
Subject: [PATCH] driver core: Don't match device with NULL of_node/fwnode
Date: Tue,  3 Dec 2024 18:02:59 -0600	[thread overview]
Message-ID: <20241204000259.2699841-1-robh@kernel.org> (raw)

It recently came up that of_find_device_by_node() will match a device
with a NULL of_node pointer. This is not desired behavior. The returned
struct device is also not deterministic.

Cc: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
---
It would be a bit more efficient to check this up front before we
iterate thru devices, but there's a number of users of these functions
and this isn't really a hot path.

I think at least device_match_acpi_dev() and device_match_acpi_handle()
should also be fixed, but am not sure about the ACPI side.
---
 drivers/base/core.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 94865c9d8adc..87d50c5f710f 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -5246,13 +5246,13 @@ EXPORT_SYMBOL_GPL(device_match_name);
 
 int device_match_of_node(struct device *dev, const void *np)
 {
-	return dev->of_node == np;
+	return np && (dev->of_node == np);
 }
 EXPORT_SYMBOL_GPL(device_match_of_node);
 
 int device_match_fwnode(struct device *dev, const void *fwnode)
 {
-	return dev_fwnode(dev) == fwnode;
+	return fwnode && (dev_fwnode(dev) == fwnode);
 }
 EXPORT_SYMBOL_GPL(device_match_fwnode);
 
-- 
2.45.2


             reply	other threads:[~2024-12-04  0:03 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-12-04  0:02 Rob Herring (Arm) [this message]
2024-12-04  9:37 ` [PATCH] driver core: Don't match device with NULL of_node/fwnode Greg Kroah-Hartman
2024-12-09 23:47   ` Brian Norris
2024-12-10 12:33     ` Rob Herring
2024-12-10 19:17       ` Brian Norris

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