From 9b22c17a3cc5f61b195da624cbb48634b4e42055 Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Tue, 18 Jan 2022 11:34:04 -0600 Subject: [PATCH] of: Check 'of_node_reused' flag on of_match_device() Commit 0f153a1b8193 ("usb: chipidea: Set the DT node on the child device") caused the child device to match on the parent driver instead of the child's driver since the child's DT node pointer matched. The worst case result is a loop of the parent driver probing another instance and creating yet another child device eventually exhausting the stack. If the child driver happens to match first, then everything works fine. A device sharing the DT node should never do DT based driver matching, so let's simply check of_node_reused in of_match_device() to prevent that. Fixes: 0f153a1b8193 ("usb: chipidea: Set the DT node on the child device") Link: https://lore.kernel.org/all/20220114105620.GK18506@ediswmail.ad.cirrus.com/ Reported-by: Charles Keepax Cc: Frank Rowand Cc: Arnd Bergmann Cc: Tony Lindgren Cc: Greg Kroah-Hartman Cc: Peter Chen Tested-by: Charles Keepax Signed-off-by: Rob Herring Link: https://lore.kernel.org/r/20220118173404.1891800-1-robh@kernel.org --- drivers/of/device.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/of/device.c b/drivers/of/device.c index b0800c260f64..874f031442dc 100644 --- a/drivers/of/device.c +++ b/drivers/of/device.c @@ -28,7 +28,7 @@ const struct of_device_id *of_match_device(const struct of_device_id *matches, const struct device *dev) { - if ((!matches) || (!dev->of_node)) + if (!matches || !dev->of_node || dev->of_node_reused) return NULL; return of_match_node(matches, dev->of_node); } -- 2.20.1