From 4363b68155c8070ab3da4a69d3f6da72a5ae2ff4 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 b110b43e8fb3 ("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: b110b43e8fb3 ("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 b0800c260f64a..874f031442dc7 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); } -- 2.39.5