From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpout-02.galae.net (smtpout-02.galae.net [185.246.84.56]) (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 DFDB62F83B7 for ; Mon, 26 Jan 2026 08:51:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.246.84.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769417520; cv=none; b=eSnh4STSM/7EDgh66Sd6I65l2F2QJJAVsr0d/SwkfpSTs15zAjfwfKhkoFj3VoUpbDiKq0TnxPLn3KPb7TCCMNNtbeP0Za5YCcRkhx4onrovRCwOl0wKozcMDz6I6fMA9fHjC1Bxw0UFN816T1fa0O9qQHq8jjbu8v6+4d76qB8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769417520; c=relaxed/simple; bh=JUG/fmK2RVt4yTO2i7fNlfhJP1TZvqM8Z2olo81C66M=; h=Mime-Version:Content-Type:Date:Message-Id:Cc:To:From:Subject: References:In-Reply-To; b=Sj4F1dxgaXFRNvB9zKcxLGze8qF6330VMUiVyPDuTzmZqi2w9BZ0kFx8mIL3eyT5br+yfGkocKVZkp7JY+HFAPLqbpMbcTpbQWCSvxZmNGI7MiadriJ3grH20/Gs9T9RU2Kn1NRmxA+2PwG0VflDCvy7LEWWsi6IPDeD+7csYVA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=QedPXVXD; arc=none smtp.client-ip=185.246.84.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="QedPXVXD" Received: from smtpout-01.galae.net (smtpout-01.galae.net [212.83.139.233]) by smtpout-02.galae.net (Postfix) with ESMTPS id 7E1A41A2A52; Mon, 26 Jan 2026 08:51:56 +0000 (UTC) Received: from mail.galae.net (mail.galae.net [212.83.136.155]) by smtpout-01.galae.net (Postfix) with ESMTPS id 45F5960717; Mon, 26 Jan 2026 08:51:56 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id C0EF6119A80E2; Mon, 26 Jan 2026 09:51:50 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=dkim; t=1769417515; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:in-reply-to:references; bh=YoimUg/B3WMdwPjCRvv8ClMn1Rr3hFGXgkVjA9JOOIg=; b=QedPXVXDwD6tu/9yJqyZ7TIZOoQUoEcFq8esUex1XnWQ/7sm1bFOA2z39idJnnow/kk7jh 4bX3+4Bql4HHg0wqoLaFx8rcPJlzoP4Ec7NI8I1sc3nY7unHATPwtp81uuyUwggtYUNuVF I11hqr3BcWARPJ5sA2i+jelLE8m0w/eeN3y3bC4ZDSuxCIlAw/aivEBPr+4u20+WMlshVO qfnQreqggUqpQoXr5MSEXcPPNYDOPot6IY7nWQSIqHWMNv8qoIQB16jWyOB9bin6jWH+x+ jXD8zr35RSom94S4/PC3dmjDMKQYOvxdKgb5Wjd4Lu4JkspNxzPyBAQyrPRTmg== Precedence: bulk X-Mailing-List: imx@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=UTF-8 Date: Mon, 26 Jan 2026 09:51:49 +0100 Message-Id: Cc: , , , To: "Liu Ying" , "Andrzej Hajda" , "Neil Armstrong" , "Robert Foss" , "Laurent Pinchart" , "Jonas Karlman" , "Jernej Skrabec" , "Maarten Lankhorst" , "Maxime Ripard" , "Thomas Zimmermann" , "David Airlie" , "Simona Vetter" , "Shawn Guo" , "Sascha Hauer" , "Pengutronix Kernel Team" , "Fabio Estevam" From: "Luca Ceresoli" Subject: Re: [PATCH 3/3] drm/bridge: imx8qxp-pixel-combiner: Fix bailout for imx8qxp_pc_bridge_probe() X-Mailer: aerc 0.20.1 References: <20260123-imx8qxp-drm-bridge-fixes-v1-0-8bb85ada5866@nxp.com> <20260123-imx8qxp-drm-bridge-fixes-v1-3-8bb85ada5866@nxp.com> <42f86084-5200-4dc0-86a7-4719d7d19cf7@nxp.com> In-Reply-To: <42f86084-5200-4dc0-86a7-4719d7d19cf7@nxp.com> X-Last-TLS-Session-Version: TLSv1.3 On Mon Jan 26, 2026 at 9:47 AM CET, Liu Ying wrote: > > > On Mon, Jan 26, 2026 at 09:33:38AM +0100, Luca Ceresoli wrote: >> On Fri Jan 23, 2026 at 10:22 AM CET, Liu Ying wrote: >>> In case the channel0 is unavailable and bailing out from free_child is >>> needed when we fail to add a DRM bridge for the available channel1, >>> pointer pc->ch[0] in the bailout path would be NULL and it would be >>> dereferenced as pc->ch[0]->bridge.next_bridge. Fix this by checking >>> pc->ch[0] before dereferencing it. >> >> Thanks for checking this code and providing fixes! These drivers have a >> complex code path so I had a hard time in following the logic without ne= ing >> able to test on hardware. Apologies for the issues emerged. > > Thanks for your quick review and hard work! > >> >>> Fixes: ae754f049ce1 ("drm/bridge: imx8qxp-pixel-combiner: get/put the n= ext bridge") >>> Fixes: 99764593528f ("drm/bridge: imx8qxp-pixel-combiner: convert to de= vm_drm_bridge_alloc() API") >> >> The bug was introduced by 99764593528f, while ae754f049ce1 is not changi= ng >> the bug, so for the sake of precision we can remove the first 'Fixes:' >> line. > > I added Fixes tag for ae754f049ce1 because it is the first commit which > this commit could be applied upon properly. Maybe this helps some tools > apply this commit or maybe tools are smart enough to find ae754f049ce1 > automatically? Uhm, good point, maybe it can be a useful reference for the stable team to backport the fix... Well, let's leave both lines then: Reviewed-by: Luca Ceresoli I'm applying this series perhaps tomorrow (if no one does it before). Luca -- Luca Ceresoli, Bootlin Embedded Linux and Kernel engineering https://bootlin.com