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Date: Fri, 24 Apr 2026 13:23:18 +0200
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Johan Hovold <johan@kernel.org>
Cc: "Rafael J . Wysocki" <rafael@kernel.org>,
	Danilo Krummrich <dakr@kernel.org>, driver-core@lists.linux.dev,
	linux-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: Re: [PATCH] driver core: faux: fix root device registration
Message-ID: <2026042438-mousiness-preorder-b1b9@gregkh>
References: <20260424102231.2615557-1-johan@kernel.org>
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In-Reply-To: <20260424102231.2615557-1-johan@kernel.org>

On Fri, Apr 24, 2026 at 12:22:31PM +0200, Johan Hovold wrote:
> A recent change made the faux bus root device be allocated dynamically
> but failed to provide a release function to free the memory when the
> last reference is dropped (on theoretical failure to register the device
> or bus).
> 
> Fix this by using root_device_register() instead of open coding.

Ah, good catch, I missed that, thanks!

> Also add the missing sanity check when registering faux devices to avoid
> a NULL-pointer dereference if the bus failed to register (which would
> previously have triggered a bunch of use-after-free warnings).

If the bus fails to register at boot time, we have bigger problems than
those types of warnings :)

I'll queue this up after -rc1 is out, thanks.

greg k-h