From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 E229542396; Mon, 18 Dec 2023 14:02:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="t1u83H/E" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 65F91C433C8; Mon, 18 Dec 2023 14:02:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1702908168; bh=Rg9ExuYnb+aM7Su8YeskNJIp+V/wMNTBIrKKRWsEajA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=t1u83H/E30jAugSoK2lXjoRaKy10Xgpl2EPRrVl3/awuyifVw3+mUWnkV2xOk1I+H fh22n+iqhqj949rvCHGhz3N6XmCpr8avS4NvGIHLYfzr0Qdnxtlp46IBHjlacglk5d t6T0tXRJeCA+MSCiUUfAnHdjE9casU6MkIU0nUQg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Michael Walle , "=?UTF-8?q?N=C3=ADcolas=20F . =20R . =20A . =20Prado?=" , AngeloGioacchino Del Regno , Eugen Hristev , Chun-Kuang Hu , Sasha Levin Subject: [PATCH 6.6 078/166] drm/mediatek: fix kernel oops if no crtc is found Date: Mon, 18 Dec 2023 14:50:44 +0100 Message-ID: <20231218135108.528906417@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231218135104.927894164@linuxfoundation.org> References: <20231218135104.927894164@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Michael Walle [ Upstream commit 4662817aed5a9d6c695658d0105d8ff4b84ac6cb ] 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 Link: https://patchwork.kernel.org/project/dri-devel/patch/20230905084922.3908121-1-mwalle@kernel.org/ Signed-off-by: Chun-Kuang Hu Signed-off-by: Sasha Levin --- 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 2d6a979afe8f9..cdd506c803733 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c @@ -421,6 +421,7 @@ 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()) @@ -495,7 +496,9 @@ 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"); -- 2.43.0