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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8FA06C88E77 for ; Mon, 26 Jan 2026 08:52:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:References: Subject:From:To:Cc:Message-Id:Date:Content-Type:Content-Transfer-Encoding: Mime-Version:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=YoimUg/B3WMdwPjCRvv8ClMn1Rr3hFGXgkVjA9JOOIg=; b=L25YL6bhgOPyE9tkmkI7j4bzIi IzL9CqXVEr+P79mVwtSKiSH3z0SGIAVLgrexbl4t6i0qVgoJBpfr0AQ4xrZzmlLTTdE+ISJddyTiW ZT/oWcpcb9su8axM9J0peDYdvTBf0bVbYaKKR/rQppjb9Mw2ijrtEM4+UrDIiqFRYEpuzDklSwZVY JR1Dl6QcoBL1Rbw0V7Zl6IetUfk8JY8PhCO//wOd0EF5pn0D2gjL3IRQzyKJHOcjGR6Wp3S1f6JES UgN40Qcek7qZ0uL0h7dnfPFL8FXqgTqSXcnpUiWBO8vythM4WcffGaGS6C53iyMoTIdftYGcZxjiK IJiLdEeg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vkIKP-0000000C7wX-3s69; Mon, 26 Jan 2026 08:52:09 +0000 Received: from smtpout-02.galae.net ([185.246.84.56]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vkIKE-0000000C7uH-3kvV for linux-arm-kernel@lists.infradead.org; Mon, 26 Jan 2026 08:52:00 +0000 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== 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 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260126_005159_071229_030D93C1 X-CRM114-Status: GOOD ( 15.09 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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