From nobody Thu Oct 2 02:15:15 2025 Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) (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 88E251F3BBB for ; Wed, 24 Sep 2025 10:37:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.251.105.195 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758710246; cv=none; b=H9MK3GSjwQvR6rJnITTyqsKl7qi5GYiZ6MccrKacWwduS86OdE/RJPf0BYzPdq77P8Rw8IoS0tBk2Poyv1iSwfaB0raxmdCapEtPGrzVda9makQKOikq6mH6O+CwTeR0tb0nSCSE5gzNelZBGalWn9uyOYk30i7gpV/c2T3quy4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758710246; c=relaxed/simple; bh=+J77+l7Lax/S/gMWseCwZwXAhPq50CEolzz2N70e80I=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JJx4ZSgqmoHlowSRLpbo3g7G/u3ORnn29By9D3k6E3tHn2b9Jju3N0Yt/l1GxR1v23b7ML7OHvwyFm/+tG5CM3puyTuwpCu9RCNmV9MZkhBl6D4+70Y91feFMeKfotFeGW643zzysrPJftWJxWzOBopj55XjGZaOLZbLwgVrbpk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b=KkW8jzA0; arc=none smtp.client-ip=148.251.105.195 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b="KkW8jzA0" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1758710238; bh=+J77+l7Lax/S/gMWseCwZwXAhPq50CEolzz2N70e80I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KkW8jzA0iWKXbsQJ8Ha4JsBLSVqztaLIMJZEiGGEJrBZmcrvem0mQSqvMpvJS5lYU 8Qq4eMK06HQuKWy/MtfE6+HFB3QONf58p4MG5fr2ur3BxLFvEEgj7RM3w04Kn3nOzT VIfjflLhf1kM05TtORCZqVdVPH1BwKvIMLlBuwTLaq7O+LhIBYSvLIIgnxbwo0z4VV axvVN3xCGMy8d5eSDUY9iu57iv+ncEk2106dOnJWno+hvi3/QirtMDf5bAC/6kPPIh l3HM48U27K4KxV6ITBreCSlXOZ+Thggi49rECVNwwnkL5MEEIRB4z/L+RRkULyI2Hg Jr3Cu+Ur8UL+g== Received: from IcarusMOD.eternityproject.eu (2-237-20-237.ip236.fastwebnet.it [2.237.20.237]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: kholk11) by bali.collaboradmins.com (Postfix) with ESMTPSA id 06AAF17E12E4; Wed, 24 Sep 2025 12:37:17 +0200 (CEST) From: AngeloGioacchino Del Regno To: chunkuang.hu@kernel.org Cc: p.zabel@pengutronix.de, airlied@gmail.com, simona@ffwll.ch, matthias.bgg@gmail.com, angelogioacchino.delregno@collabora.com, dmitry.osipenko@collabora.com, granquet@baylibre.com, rex-bc.chen@mediatek.com, ck.hu@mediatek.com, amergnat@baylibre.com, djkurtz@chromium.org, littlecvr@chromium.org, bibby.hsieh@mediatek.com, dri-devel@lists.freedesktop.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kernel@collabora.com Subject: [PATCH 2/3] drm/mediatek: mtk_disp_ovl: Enable/disable interrupt on bind/unbind Date: Wed, 24 Sep 2025 12:37:07 +0200 Message-ID: <20250924103708.19071-3-angelogioacchino.delregno@collabora.com> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20250924103708.19071-1-angelogioacchino.delregno@collabora.com> References: <20250924103708.19071-1-angelogioacchino.delregno@collabora.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The OVL driver is installing an ISR in the probe function but, if the component is not bound yet, the interrupt handler may call the vblank_cb ahead of time (while probing other drivers) or too late (while removing other drivers), possibly accessing memory that it should not try to access by reusing stale pointers. In order to fix this, add a new `irq` member to struct mtk_disp_ovl and then set the NOAUTOEN flag to the irq before installing the ISR to manually call enable_irq() and disable_irq() in the bind and unbind callbacks respectively. Fixes: 119f5173628a ("drm/mediatek: Add DRM Driver for Mediatek SoC MT8173.= ") Link: https://lore.kernel.org/r/20250402083628.20111-5-angelogioacchino.del= regno@collabora.com Signed-off-by: AngeloGioacchino Del Regno --- drivers/gpu/drm/mediatek/mtk_disp_ovl.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c b/drivers/gpu/drm/medi= atek/mtk_disp_ovl.c index e0236353d499..8e20b45411fc 100644 --- a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c +++ b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c @@ -161,6 +161,7 @@ struct mtk_disp_ovl { struct drm_crtc *crtc; struct clk *clk; void __iomem *regs; + int irq; struct cmdq_client_reg cmdq_reg; const struct mtk_disp_ovl_data *data; void (*vblank_cb)(void *data); @@ -594,12 +595,18 @@ void mtk_ovl_bgclr_in_off(struct device *dev) static int mtk_disp_ovl_bind(struct device *dev, struct device *master, void *data) { + struct mtk_disp_ovl *priv =3D dev_get_drvdata(dev); + + enable_irq(priv->irq); return 0; } =20 static void mtk_disp_ovl_unbind(struct device *dev, struct device *master, void *data) { + struct mtk_disp_ovl *priv =3D dev_get_drvdata(dev); + + disable_irq(priv->irq); } =20 static const struct component_ops mtk_disp_ovl_component_ops =3D { @@ -611,16 +618,15 @@ static int mtk_disp_ovl_probe(struct platform_device = *pdev) { struct device *dev =3D &pdev->dev; struct mtk_disp_ovl *priv; - int irq; int ret; =20 priv =3D devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; =20 - irq =3D platform_get_irq(pdev, 0); - if (irq < 0) - return irq; + priv->irq =3D platform_get_irq(pdev, 0); + if (priv->irq < 0) + return priv->irq; =20 priv->clk =3D devm_clk_get(dev, NULL); if (IS_ERR(priv->clk)) @@ -640,10 +646,10 @@ static int mtk_disp_ovl_probe(struct platform_device = *pdev) priv->data =3D of_device_get_match_data(dev); platform_set_drvdata(pdev, priv); =20 - ret =3D devm_request_irq(dev, irq, mtk_disp_ovl_irq_handler, - IRQF_TRIGGER_NONE, dev_name(dev), priv); + ret =3D devm_request_irq(dev, priv->irq, mtk_disp_ovl_irq_handler, + IRQF_NO_AUTOEN, dev_name(dev), priv); if (ret < 0) - return dev_err_probe(dev, ret, "Failed to request irq %d\n", irq); + return dev_err_probe(dev, ret, "Failed to request irq %d\n", priv->irq); =20 pm_runtime_enable(dev); =20 --=20 2.51.0