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 C4A75CA0FEC for ; Fri, 1 Sep 2023 17:46:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235017AbjIARqK (ORCPT ); Fri, 1 Sep 2023 13:46:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41128 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235175AbjIARqJ (ORCPT ); Fri, 1 Sep 2023 13:46:09 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9556DE5A for ; Fri, 1 Sep 2023 10:46:06 -0700 (PDT) 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 ams.source.kernel.org (Postfix) with ESMTPS id 61B78B82515 for ; Fri, 1 Sep 2023 17:46:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0E8E9C433C8; Fri, 1 Sep 2023 17:46:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1693590364; bh=z9MFcKUA2gr9p3j7guEmqBFsjLvJtfm5s1/pUyVg+9Y=; h=From:To:Cc:Subject:Date:From; b=k/5mo1IkqXCkSxQa+gyzgn6haj2cRQXCR4ZFizjIzBSukbJhsL/7CdHHWrtyP8Oj7 fNL/IkYS/90YeimQkiMbkRZ0wdeeUxL2upgGMOcANCUa69e74yXdMux554fF+ruGqL g/ck3fVYUVmRudEeBrQHKSDTSFZwHyTVX78/BGZnhzk8OKYzv8s9nN0SFFInwrJoFs PHE2nE11z3911CIRAE8+iM9ngoCsdK1NGz3CzRYYDNFSo/zw+ICiSU0BDxbjQRzXob Dh4+rszthPUp0fkr5aqSPa6Ad8CJyxansjQXNZPogGiNsZa14qFF5RgoiD5UiU0r4C PiHkSeqVQAAzg== From: Michael Walle To: =?UTF-8?q?N=C3=ADcolas=20F=20=2E=20R=20=2E=20A=20=2E=20Prado?= , Chun-Kuang Hu , Philipp Zabel , David Airlie , Daniel Vetter , Matthias Brugger , AngeloGioacchino Del Regno Cc: "Nancy . Lin" , Frank Wunderlich , Jitao Shi , Stu Hsieh , dri-devel@lists.freedesktop.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Michael Walle Subject: [PATCH v3 1/2] drm/mediatek: fix kernel oops if no crtc is found Date: Fri, 1 Sep 2023 19:45:56 +0200 Message-Id: <20230901174557.3617839-1-mwalle@kernel.org> X-Mailer: git-send-email 2.39.2 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- 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"); -- 2.39.2