Re: [PATCH] of: Check 'of_node_reused' flag on of_match_device()

From: Rob Herring
Date: Thu Jan 20 2022 - 12:31:30 EST


On Tue, 18 Jan 2022 11:34:04 -0600, Rob Herring wrote:
> 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@xxxxxxxxxxxxxxxxxxxxxxx/
> Reported-by: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxx>
> Cc: Frank Rowand <frowand.list@xxxxxxxxx>
> Cc: Arnd Bergmann <arnd@xxxxxxxx>
> Cc: Tony Lindgren <tony@xxxxxxxxxxx>
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Cc: Peter Chen <peter.chen@xxxxxxx>
> Tested-by: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
> ---
> drivers/of/device.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>

Applied, thanks!