From nobody Thu Sep 19 23:07:30 2024 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 D643A1CDFAD for ; Tue, 27 Aug 2024 14:56:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724770561; cv=none; b=dfO0+dpyo2ATVyF7cou5YN+GtNcmhg5YA3TMPcxN925pWqvQtlqL/HwOvE5NxvBjleYSyQZGiRzjVfkto6WQsrqcaWP/cH6hE60Nwm/SfPE8t8nqj6XpD6b3Q2E2g9gZlkyiaBCo2mq3y93yaots6olPj9F1FircQTZWN4U+6O4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724770561; c=relaxed/simple; bh=xz/UXWEcxepYKNcKplNKWh6SZMhniiI0hGFc+cpA380=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=BPA8eU+FQB8HyhJOuvZVtnoi8AhCKrOpiuHvifckMDFdglmd53s4BuLqtnMC/EbMhKdYuacJQ1fIZ0ItOZ0LdiVzdjqk1Q0prqxU9X7toRzwNY2F7EKyx0C+WrK06s7Jn8K3I85+3w5XxWAZM1DrbwfnTk6n/az04LeStvFeDXY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=LT/LDSBV; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="LT/LDSBV" Received: by smtp.kernel.org (Postfix) with ESMTPS id 79CC4C4FDFD; Tue, 27 Aug 2024 14:56:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1724770560; bh=xz/UXWEcxepYKNcKplNKWh6SZMhniiI0hGFc+cpA380=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=LT/LDSBVgHCmFK5RVM4E1LVtG4IfiFWhKylo/7npYwn6ZRRh+wSqrF01UtglUvr+8 fL0Xn5wzbEf0zfJjBHsWWNHjafpdFrRk5x1QOTyHCh6EKUpQyfY8jiFoxxxo1K5eVv 4ui18Zu1hRq+BMsU1X2iwGC5dMwd/Z2mAIY8VuG3zpdBaNFcSpb0I7Irqr/a5Dml0q uvdN05ISO/59QecsCeT1v/uvxmkp1RZNE1b/Xkyojry+6jOvN4lsSeuUifr53wQUb3 XS/akLEcLPp6s9i7hw1EZIcf5aeFbchpkxeKjyc9Z7/VGY6+P3EeJWGcKqr/tf1qEx opVe0a51VpKsg== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6BB42C54734; Tue, 27 Aug 2024 14:56:00 +0000 (UTC) From: "Jason-JH.Lin via B4 Relay" Date: Tue, 27 Aug 2024 22:55:20 +0800 Subject: [PATCH v3 2/2] drm/mediatek: change config_lock from spin_lock to spin_lock_irqsave Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20240827-drm-fixup-0819-v3-2-4761005211ec@mediatek.com> References: <20240827-drm-fixup-0819-v3-0-4761005211ec@mediatek.com> In-Reply-To: <20240827-drm-fixup-0819-v3-0-4761005211ec@mediatek.com> To: Chun-Kuang Hu , AngeloGioacchino Del Regno Cc: Philipp Zabel , David Airlie , Daniel Vetter , Singo Chang , Nancy Lin , "Jason-JH.Lin" , Project_Global_Chrome_Upstream_Group@mediatek.com, dri-devel@lists.freedesktop.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org X-Mailer: b4 0.14.0 X-Developer-Signature: v=1; a=ed25519-sha256; t=1724770559; l=3389; i=jason-jh.lin@mediatek.com; s=20240718; h=from:subject:message-id; bh=qmIEDrv7vEydnkYLajQteZQg7GKHc0xz1SItk+ixJMg=; b=BMUDPPx43HxuqLgPxE38r9SfCUMKzAyjGAJfDPSQ8Fp8MAR5/tJSt8tP35PMgK/0E70FFaATs XMmR4p7wiooD3Dn/qzlUeXxxFLuDK7Kd7rIrAvazmTQhyF3ZtSK5qKg X-Developer-Key: i=jason-jh.lin@mediatek.com; a=ed25519; pk=7Hn+BnFBlPrluT5ks5tKVWb3f7O/bMBs6qEemVJwqOo= X-Endpoint-Received: by B4 Relay for jason-jh.lin@mediatek.com/20240718 with auth_id=187 X-Original-From: "Jason-JH.Lin" Reply-To: jason-jh.lin@mediatek.com From: "Jason-JH.Lin" Operations within spin_locks are limited to fast memory access and confirmation of minimum lock duration. Although using spin_lock with config_lock seems to ensure shorter hold times, it is safer to use spin_lock_irqsave due to potential deadlocks and nested interrupt scenarios in interrupt contexts. So change config_lock from spin_lock to spin_lock_irqsave. Fixes: 7f82d9c43879 ("drm/mediatek: Clear pending flag when cmdq packet is = done") Signed-off-by: Jason-JH.Lin Reviewed-by: Fei Shao --- drivers/gpu/drm/mediatek/mtk_crtc.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) diff --git a/drivers/gpu/drm/mediatek/mtk_crtc.c b/drivers/gpu/drm/mediatek= /mtk_crtc.c index b752c0b46383..d7f0926f896d 100644 --- a/drivers/gpu/drm/mediatek/mtk_crtc.c +++ b/drivers/gpu/drm/mediatek/mtk_crtc.c @@ -108,14 +108,16 @@ static void mtk_crtc_finish_page_flip(struct mtk_crtc= *mtk_crtc) =20 static void mtk_drm_finish_page_flip(struct mtk_crtc *mtk_crtc) { + unsigned long flags; + drm_crtc_handle_vblank(&mtk_crtc->base); =20 - spin_lock(&mtk_crtc->config_lock); + spin_lock_irqsave(&mtk_crtc->config_lock, flags); if (!mtk_crtc->config_updating && mtk_crtc->pending_needs_vblank) { mtk_crtc_finish_page_flip(mtk_crtc); mtk_crtc->pending_needs_vblank =3D false; } - spin_unlock(&mtk_crtc->config_lock); + spin_unlock_irqrestore(&mtk_crtc->config_lock, flags); } =20 #if IS_REACHABLE(CONFIG_MTK_CMDQ) @@ -313,16 +315,16 @@ static void ddp_cmdq_cb(struct mbox_client *cl, void = *mssg) struct mtk_crtc *mtk_crtc =3D container_of(cmdq_cl, struct mtk_crtc, cmdq= _client); struct mtk_crtc_state *state; unsigned int i; + unsigned long flags; =20 if (data->sta < 0) return; =20 state =3D to_mtk_crtc_state(mtk_crtc->base.state); =20 - spin_lock(&mtk_crtc->config_lock); - + spin_lock_irqsave(&mtk_crtc->config_lock, flags); if (mtk_crtc->config_updating) { - spin_unlock(&mtk_crtc->config_lock); + spin_unlock_irqrestore(&mtk_crtc->config_lock, flags); goto ddp_cmdq_cb_out; } =20 @@ -352,7 +354,7 @@ static void ddp_cmdq_cb(struct mbox_client *cl, void *m= ssg) mtk_crtc->pending_async_planes =3D false; } =20 - spin_unlock(&mtk_crtc->config_lock); + spin_unlock_irqrestore(&mtk_crtc->config_lock, flags); =20 ddp_cmdq_cb_out: =20 @@ -585,12 +587,13 @@ static void mtk_crtc_update_config(struct mtk_crtc *m= tk_crtc, bool needs_vblank) struct mtk_drm_private *priv =3D crtc->dev->dev_private; unsigned int pending_planes =3D 0, pending_async_planes =3D 0; int i; + unsigned long flags; =20 mutex_lock(&mtk_crtc->hw_lock); =20 - spin_lock(&mtk_crtc->config_lock); + spin_lock_irqsave(&mtk_crtc->config_lock, flags); mtk_crtc->config_updating =3D true; - spin_unlock(&mtk_crtc->config_lock); + spin_unlock_irqrestore(&mtk_crtc->config_lock, flags); =20 if (needs_vblank) mtk_crtc->pending_needs_vblank =3D true; @@ -645,9 +648,9 @@ static void mtk_crtc_update_config(struct mtk_crtc *mtk= _crtc, bool needs_vblank) mbox_client_txdone(mtk_crtc->cmdq_client.chan, 0); } #endif - spin_lock(&mtk_crtc->config_lock); + spin_lock_irqsave(&mtk_crtc->config_lock, flags); mtk_crtc->config_updating =3D false; - spin_unlock(&mtk_crtc->config_lock); + spin_unlock_irqrestore(&mtk_crtc->config_lock, flags); =20 mutex_unlock(&mtk_crtc->hw_lock); } --=20 2.43.0