From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5C14FC4332F for ; Wed, 23 Nov 2022 09:11:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237184AbiKWJLM (ORCPT ); Wed, 23 Nov 2022 04:11:12 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51750 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237241AbiKWJKw (ORCPT ); Wed, 23 Nov 2022 04:10:52 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DAC4F193C6 for ; Wed, 23 Nov 2022 01:10:43 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 77A9161B43 for ; Wed, 23 Nov 2022 09:10:43 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5F48BC433C1; Wed, 23 Nov 2022 09:10:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1669194642; bh=ZyIsjk83RiWDYobLCizAPcbpgtskiaSiiPgPFhWC6U8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lDsitFP0Il4W7F7osnWhVn/1l+2XzhQBgf1MoHmJ/l7WYCWT8ZtkGhBE8Cx8kw/iM 9uNvLm9MjVySsRy8xj7tQeUQTrFJqPbKIlsVJElKsexFhI30HDzFEpC2FfXKMuU2ZJ 7NO2Ub0+U99oq/D3+34F0IFdpQsfkv7hSsBBYMEI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yuan Can , Maxime Ripard , Sasha Levin Subject: [PATCH 5.4 020/156] drm/vc4: Fix missing platform_unregister_drivers() call in vc4_drm_register() Date: Wed, 23 Nov 2022 09:49:37 +0100 Message-Id: <20221123084558.657301431@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221123084557.816085212@linuxfoundation.org> References: <20221123084557.816085212@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Yuan Can [ Upstream commit cf53db768a8790fdaae2fa3a81322b080285f7e5 ] A problem about modprobe vc4 failed is triggered with the following log given: [ 420.327987] Error: Driver 'vc4_hvs' is already registered, aborting... [ 420.333904] failed to register platform driver vc4_hvs_driver [vc4]: -16 modprobe: ERROR: could not insert 'vc4': Device or resource busy The reason is that vc4_drm_register() returns platform_driver_register() directly without checking its return value, if platform_driver_register() fails, it returns without unregistering all the vc4 drivers, resulting the vc4 can never be installed later. A simple call graph is shown as below: vc4_drm_register() platform_register_drivers() # all vc4 drivers are registered platform_driver_register() driver_register() bus_add_driver() priv = kzalloc(...) # OOM happened # return without unregister drivers Fixing this problem by checking the return value of platform_driver_register() and do platform_unregister_drivers() if error happened. Fixes: c8b75bca92cb ("drm/vc4: Add KMS support for Raspberry Pi.") Signed-off-by: Yuan Can Signed-off-by: Maxime Ripard Link: https://patchwork.freedesktop.org/patch/msgid/20221103014705.109322-1-yuancan@huawei.com Signed-off-by: Sasha Levin --- drivers/gpu/drm/vc4/vc4_drv.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c index 0d78ba017a29..36688a56c91c 100644 --- a/drivers/gpu/drm/vc4/vc4_drv.c +++ b/drivers/gpu/drm/vc4/vc4_drv.c @@ -392,7 +392,12 @@ static int __init vc4_drm_register(void) if (ret) return ret; - return platform_driver_register(&vc4_platform_driver); + ret = platform_driver_register(&vc4_platform_driver); + if (ret) + platform_unregister_drivers(component_drivers, + ARRAY_SIZE(component_drivers)); + + return ret; } static void __exit vc4_drm_unregister(void) -- 2.35.1