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 5F48EC83F14 for ; Tue, 29 Aug 2023 13:21:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235956AbjH2NUo (ORCPT ); Tue, 29 Aug 2023 09:20:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58994 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235949AbjH2NUX (ORCPT ); Tue, 29 Aug 2023 09:20:23 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 911E1184 for ; Tue, 29 Aug 2023 06:20:21 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 26A7365266 for ; Tue, 29 Aug 2023 13:20:21 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7B4F3C433C8; Tue, 29 Aug 2023 13:20:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1693315220; bh=fokDp0Y3EnAwlAaygTWGT0A7Dg/k0huj36SykKsEO6Y=; h=From:To:Cc:Subject:Date:From; b=pC8tYIYstToTiPlNCSA6rH4DvNMTO8TuwNqOFxP0EK8hrjighEkXO7ppL56nIsaMU v2gR7SvJLwOMeEwvmIQc/qSBRpSNoAkt7DCnNzMrFGIKwbqwWbr07vBkBpztoJcQT8 WwzHHgYxVZppoh2f2VrfdChGUhOrGq3K2EaAxbJvLYUQ+AL0NfU1BDvaGqy1xBwbjG kyXmCWU5FY6aTpDr6RBDvO+WZHCkPKG/boO9nyXUUAolXIATWsPbhIMnNxVGSo17kI AW/EeIssueZgLVJ4o3WRNrKIdYByJrr5eOufNlpnNqFi+RBKwYJjL4E3tWK5Vfr+i/ kKLGDNrlMCFTw== 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 1/2] drm/mediathek: fix kernel oops if no crtc is found Date: Tue, 29 Aug 2023 15:19:40 +0200 Message-Id: <20230829131941.3353439-1-mwalle@kernel.org> X-Mailer: git-send-email 2.39.2 MIME-Version: 1.0 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 not 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 --- 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