From patchwork Tue Sep 5 08:49:21 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Michael Walle X-Patchwork-Id: 13374393 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 3ABC0C83F2C for ; Tue, 5 Sep 2023 08:49:38 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 6475210E464; Tue, 5 Sep 2023 08:49:37 +0000 (UTC) Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by gabe.freedesktop.org (Postfix) with ESMTPS id DD1E510E464 for ; Tue, 5 Sep 2023 08:49:34 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 3C5D460A6B; Tue, 5 Sep 2023 08:49:34 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 93213C433C7; Tue, 5 Sep 2023 08:49:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1693903773; bh=Lf9Emcq2vJ47o82Ba07mxnuB6z6CRgChEACdlF49c/k=; h=From:To:Cc:Subject:Date:From; b=sXQdyRmaLVEwpQ+xaPGniJhgMeDRTmARk45pVck1hgPeegSPl4LPhZSfT8/kVnDbE B3vY2pcQOO/Q79nHzLzYHlyySBl96yA0piLcyKvoWiVbg9Wx3KtDH51HTjdjGlwCAX U+7H4orgwNXloi2VJwXEjxYbKOlziEPlTGzJdt/C6ckh2cww99531X+tcjY9gj6Ok9 +K1BO85H9UoJRwRwj0x1ZDZBtjanrx8Js3Eo99S8fpESIgC3UOBjI+wvFR843h5Tuq Ds45ieFHjGgGIdyU102bKa58TXzpFly+8BYeNa5ay3/ipKZeCpbIM0XUDsDeezqeWb NFmA0PfnLZmdA== From: Michael Walle To: =?utf-8?q?N=C3=ADcolas_F_=2E_R_=2E_A_=2E_Prado?= , Chun-Kuang Hu , Philipp Zabel , David Airlie , Daniel Vetter , Matthias Brugger , AngeloGioacchino Del Regno Subject: [PATCH v4 1/2] drm/mediatek: fix kernel oops if no crtc is found Date: Tue, 5 Sep 2023 10:49:21 +0200 Message-Id: <20230905084922.3908121-1-mwalle@kernel.org> X-Mailer: git-send-email 2.39.2 MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jitao Shi , Frank Wunderlich , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, "Nancy . Lin" , linux-mediatek@lists.infradead.org, Stu Hsieh , Michael Walle , linux-arm-kernel@lists.infradead.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" drm_crtc_from_index(0) might return NULL if there are no CRTCs registered at all which will lead to a kernel oops in mtk_drm_crtc_dma_dev_get(). Add the missing return value check. Fixes: 0d9eee9118b7 ("drm/mediatek: Add drm ovl_adaptor sub driver for MT8195") Signed-off-by: Michael Walle Reviewed-by: Nícolas F. R. A. Prado Tested-by: Nícolas F. R. A. Prado Reviewed-by: AngeloGioacchino Del Regno Tested-by: Eugen Hristev Reviewed-by: Eugen Hristev --- v4: - collected tags v3: - none v2: - collected tags - fixed typos --- drivers/gpu/drm/mediatek/mtk_drm_drv.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c index 93552d76b6e7..2c582498817e 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c @@ -420,6 +420,7 @@ static int mtk_drm_kms_init(struct drm_device *drm) struct mtk_drm_private *private = drm->dev_private; struct mtk_drm_private *priv_n; struct device *dma_dev = NULL; + struct drm_crtc *crtc; int ret, i, j; if (drm_firmware_drivers_only()) @@ -494,7 +495,9 @@ static int mtk_drm_kms_init(struct drm_device *drm) } /* Use OVL device for all DMA memory allocations */ - dma_dev = mtk_drm_crtc_dma_dev_get(drm_crtc_from_index(drm, 0)); + crtc = drm_crtc_from_index(drm, 0); + if (crtc) + dma_dev = mtk_drm_crtc_dma_dev_get(crtc); if (!dma_dev) { ret = -ENODEV; dev_err(drm->dev, "Need at least one OVL device\n");