From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1037C39D6FA; Tue, 6 Oct 2026 09:56:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791280619; cv=none; b=ZjKcQjHDc+90GuMdKmR53uQ2VoRHIVqOGxtY6amomCoXHRdXrphKXKglrS8jhenLEEWj3+dQ03m9pnhLGHMOwjCqZHyGrvGkwKHJzgz8hNfaRzmGm+bM+gH67Gt0czeUKNLIrNSXK31IL8fH9fO/hz/+c0bI1xsVn0jb7XK7Yw0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791280619; c=relaxed/simple; bh=AleYvG/qq8AFQ+xETaiTdk8DrGfhb9/hI1aqS/R4jxM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=cKwaKaevPfDz1BYSJpIQmbe6YW9tBT2rHFb3tXl9AqWxqfs+xL1uBzfMR9epWWqMope2eEgNLgt+XcmPGIomHb9bKWS1bHV2XtbvMvFh5JrGN/aDkwQKuBhJXerTi1JNr2ax5jdqQpDOSMiYdwj5mi7/muoOeiM4MJwZKGBCAa4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Q4xn/b42; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Q4xn/b42" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D999F1F000FF; Tue, 6 Oct 2026 09:56:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1791280617; bh=AleYvG/qq8AFQ+xETaiTdk8DrGfhb9/hI1aqS/R4jxM=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=Q4xn/b42sovP3gmwYnSwgeQmC5kz6pxAhQrc8udqr/1e3D/IMfo3ktg9Na6UAH1bJ 6lLvvsap7sWw4PZ946I+FVXPYBIUbUPTp/87dqWluvS7mV7IjoNvyXgkretQiKX91z tnOfvqPjon8/99vc+aG2KW4VJrr5Linqb0Xn64shBx6Lv75hkp2q4DG2LU2l84YwkU O5fZG/m99eKn1pyoiqefHqdt+yiBibJU0rItAfYEj0A5zfOXlji8mDTOX7cNoCNJgN ZB1rt/k2G8gHOF4VCWXmnlspYgFq9dzCncCh+TH4ro1aZ/bSy8dNyshYWOi5KifTCZ eYWI6NFy19TLg== Date: Tue, 6 Oct 2026 10:56:53 +0100 From: Daniel Thompson To: Myeonghun Pak Cc: Lee Jones , Jingoo Han , Helge Deller , dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, Ijae Kim Subject: Re: [PATCH] backlight: lm3630a: Cancel delayed work before destroying workqueue Message-ID: References: <20261003030439.599330-1-mhun512@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261003030439.599330-1-mhun512@gmail.com> On Fri, Oct 02, 2026 at 11:04:39PM -0400, Myeonghun Pak wrote: > The interrupt handler queues delayed work to read the interrupt status. > After free_irq() stops the producer, this work can still be waiting on its > timer. destroy_workqueue() cannot drain delayed work that has not yet been > queued by its timer, so the timer can outlive both the workqueue and the > devm-allocated chip containing the work. > > Cancel the delayed work synchronously after freeing the IRQ and before > destroying the workqueue. This also waits for any running status read to > finish before the chip's resources are released. > > This issue was identified during our ongoing static-analysis research > while reviewing kernel code. > > Fixes: 0c2a665a648e ("backlight: add Backlight driver for lm3630 chip") > Cc: stable@vger.kernel.org > Assisted-by: LLM > Co-developed-by: Ijae Kim > Signed-off-by: Ijae Kim > Signed-off-by: Myeonghun Pak Reviewed-by: Daniel Thompson (RISCstar) Daniel.