Received-SPF: pass (google.com: domain of linux-kernel+bounces-75847-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.48.161 as permitted sender) client-ip=147.75.48.161;
From: "Wu, Wentong" <wentong.wu@intel.com>
To: Sakari Ailus <sakari.ailus@linux.intel.com>
CC: Hans de Goede <hdegoede@redhat.com>, "Winkler, Tomas"
	<tomas.winkler@intel.com>, Arnd Bergmann <arnd@arndb.de>, Greg Kroah-Hartman
	<gregkh@linuxfoundation.org>, "linux-kernel@vger.kernel.org"
	<linux-kernel@vger.kernel.org>
Subject: RE: [PATCH v2 1/3] mei: vsc: Call wake_up() in the threaded IRQ
 handler
Thread-Topic: [PATCH v2 1/3] mei: vsc: Call wake_up() in the threaded IRQ
 handler
Thread-Index: AQHaY24BYYe2VBw7MEGkR20e9s7pwrEVtjmQ
Date: Thu, 22 Feb 2024 03:26:18 +0000
Message-ID: <MW5PR11MB5787130A75404600F47A7D9C8D562@MW5PR11MB5787.namprd11.prod.outlook.com>
References: <20240219195807.517742-1-sakari.ailus@linux.intel.com>
 <20240219195807.517742-2-sakari.ailus@linux.intel.com>
In-Reply-To: <20240219195807.517742-2-sakari.ailus@linux.intel.com>
Accept-Language: en-US
Content-Language: en-US
x-ms-exchange-antispam-messagedata-chunkcount: 1
x-ms-exchange-antispam-messagedata-0: =?us-ascii?Q?JhYbEXZ538/tnyl/7QmJNEuVPScP4Fu4sOYx4Ai5DjIsdeiGgZ0PKOQrpDI6?=
 =?us-ascii?Q?3ECFFqlyC76uLEnYMo2/100rRokjLNZY+ZEZ5Brjv3u5KFhoGlmkixfhPIz+?=
 =?us-ascii?Q?AXWB9mBt9Gu/3G7mDAn1x2DZTQCROkQeHBH3HFSpLuE5rS6PToMMYljmb/+G?=
 =?us-ascii?Q?L+8Zi5QNGFNHTojnsnT3tcVSrxZiPOxAq+A+CxHs87/l8lsPP7F+wD7XbVk4?=
 =?us-ascii?Q?nroFmaY01ecq/OtyWtr06zDMAtvOkps4rz31QYPZVeVnM1Bw8FZcqdzImwq4?=
 =?us-ascii?Q?EFLnwLQlXwsXa9iKG3n00R3o+dTakMJU7aLgfiSKTvallfFRQWervz21Rd2t?=
 =?us-ascii?Q?cx3qe1l1ufS+0pSL3w8T0bJp1y1jRppYl/udI/uC7OnytFYWNWhAzaiUp4jF?=
 =?us-ascii?Q?vTqgGEYqVA9TzFP+HaRFDXhG+urehf9O048GDC1Eu0vfWdfsUCTYs17kKLfD?=
 =?us-ascii?Q?Gh4B02Yo0t09PKO8Kcww07fDvLxD/MWgBfbVsruwjVIQaQ4SVKyLCjYAVfAd?=
 =?us-ascii?Q?vQHEXnmeVzv7Juw/f0QL8N7sf9QfgAmaf97bvSSvsQ6c4VwbRoVZaLdmR/qD?=
 =?us-ascii?Q?JLhe4f3zS+Fxp7XDfa6HXYvOH/dLNdFRhqrgjV1fU5Gnbm+znyONZ+SMT9eK?=
 =?us-ascii?Q?xWem71ZQgy9OxIKOmqCYvhht1JajU2CBLdJKeRzDshW01oTqyHR3Yd5NB3CN?=
 =?us-ascii?Q?cU2HFS8uIpXvEzCpqku04PFC9vNQJ3ZeUXlslrzSlacVSpA4rXiDh/bu40Gq?=
 =?us-ascii?Q?gUCJMO4PL/1ZZeRX0qtC+posst9tsdeGw0lZPYIVCeB3LCAFK506BtF/PSy5?=
 =?us-ascii?Q?shMPq5AEQSn64wc359nqPDDjQYN8M4R91fW5AYIF1MOgXvP5ROOc+wF/hUBf?=
 =?us-ascii?Q?XndIBSN5lZIZWwOm8uM3P+s7xcblctCWSkXBFE1xhwbRl09shOPIreCSefyM?=
 =?us-ascii?Q?nWbXwvM0UVRurLGQf37V56RF6QIQcBhRl50Qapeizs6JF22wlPHL09CX8UOZ?=
 =?us-ascii?Q?AE8gwvol4dE7oXXSsdG0kKu1NUJR+MMj2gGrfWlE9LbROWWzWOhNTDim4ube?=
 =?us-ascii?Q?gTxHCqPyyxTfsMcRD52cRKzkMZ2Tk98z8tuefZWdTj5JPDFs73/sJh3MDjrq?=
 =?us-ascii?Q?rdfvvTY924z0UCR7Xoqf4GNFcprXSzsACqQbAWmLcE3HvkNuHIdVRnw14uFd?=
 =?us-ascii?Q?zzGcc5gxr75iyf2uqvD6AnsJL0RnRDBku0iWWFKcztbdZbXLtqrfY1SLYtWO?=
 =?us-ascii?Q?AGYEwia264a2xFXWYOFBK8lPvy+uaG0HP9w9Pb0NCebicAM1h7mAnw94Xcij?=
 =?us-ascii?Q?aykiuesi964hU4Mzniz5NAdMrjzZnfALMfvJSY4ttKyS5XLEga2Q2puak+xg?=
 =?us-ascii?Q?j6D6/R6WaEImTg94Hv7wTAUASM7QMcw7i0ykiO5R+E62NFBRGXEasAdZX7QP?=
 =?us-ascii?Q?j3t72QfHkuzMHrTd5WOZpbMkSHiCXi4ewQiOD+Cc1f+ytbcXxcDhBiM9q0CP?=
 =?us-ascii?Q?/lbBpRzpiEqGEXUOggQcVjpc/ZouaXg0cqBk9FENBlEB3yGnRjk8qClig+A5?=
 =?us-ascii?Q?a/VLyC5aHfq238iJV+JotlfOZMzfpR+IoOV4nD7i?=
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
Precedence: bulk
X-Mailing-List: linux-kernel@vger.kernel.org
List-Id: <linux-kernel.vger.kernel.org>
List-Subscribe: <mailto:linux-kernel+subscribe@vger.kernel.org>
List-Unsubscribe: <mailto:linux-kernel+unsubscribe@vger.kernel.org>
MIME-Version: 1.0
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-AuthSource: MW5PR11MB5787.namprd11.prod.outlook.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 3a137114-8e3f-4936-255d-08dc335608e5
X-MS-Exchange-CrossTenant-originalarrivaltime: 22 Feb 2024 03:26:18.8785
 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 46c98d88-e344-4ed4-8496-4ed7712e255d
X-MS-Exchange-CrossTenant-mailboxtype: HOSTED
X-MS-Exchange-CrossTenant-userprincipalname: VZ6zWx1bmo0tQmyPMuLw+zX4NgQUYjnIbsc9jeKvIq0VZNzTSZbf3+Mfn15VA6nGPUI2+idF7ASYVcSTApEGbw==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR11MB7500
X-OriginatorOrg: intel.com

> From: Sakari Ailus <sakari.ailus@linux.intel.com>
>=20
> The hard IRQ handler vsc_tp_irq() is called with a raw spinlock taken.
> wake_up() acquires a spinlock, a sleeping lock on PREEMPT_RT.

Does this mean we can't use wake_up() in isr?=20

BR,
Wentong

> This leads to sleeping in atomic context.
>=20
> Move the wake_up() call to the threaded IRQ handler vsc_tp_thread_isr()
> where it can be safely called.
>=20
> Fixes: 566f5ca97680 ("mei: Add transport driver for IVSC device")
> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> ---
>  drivers/misc/mei/vsc-tp.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>=20
> diff --git a/drivers/misc/mei/vsc-tp.c b/drivers/misc/mei/vsc-tp.c index
> 6f4a4be6ccb5..2b69ada9349e 100644
> --- a/drivers/misc/mei/vsc-tp.c
> +++ b/drivers/misc/mei/vsc-tp.c
> @@ -416,8 +416,6 @@ static irqreturn_t vsc_tp_isr(int irq, void *data)
>=20
>  	atomic_inc(&tp->assert_cnt);
>=20
> -	wake_up(&tp->xfer_wait);
> -
>  	return IRQ_WAKE_THREAD;
>  }
>=20
> @@ -425,6 +423,8 @@ static irqreturn_t vsc_tp_thread_isr(int irq, void
> *data)  {
>  	struct vsc_tp *tp =3D data;
>=20
> +	wake_up(&tp->xfer_wait);
> +
>  	if (tp->event_notify)
>  		tp->event_notify(tp->event_notify_context);
>=20
> --
> 2.39.2