From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <stable-owner@vger.kernel.org>
Received: from mail-bl2on0057.outbound.protection.outlook.com ([65.55.169.57]:60879
	"EHLO na01-bl2-obe.outbound.protection.outlook.com"
	rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP
	id S1751646AbcESWuQ (ORCPT <rfc822;stable@vger.kernel.org>);
	Thu, 19 May 2016 18:50:16 -0400
Message-ID: <573E431E.5000405@caviumnetworks.com>
Date: Thu, 19 May 2016 15:50:06 -0700
From: David Daney <ddaney@caviumnetworks.com>
MIME-Version: 1.0
To: Scot Doyle <lkml14@scotdoyle.com>
CC: Tomi Valkeinen <tomi.valkeinen@ti.com>,
	Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>,
	David Daney <david.daney@cavium.com>,
	Ming Lei <ming.lei@canonical.com>,
	Dann Frazier <dann.frazier@canonical.com>,
	Jeremy Kerr <jk@ozlabs.org>,
	Peter Hurley <peter@hurleysoftware.com>,
	Pavel Machek <pavel@ucw.cz>, Jonathan Liu <net147@gmail.com>,
	Alistair Popple <alistair@popple.id.au>,
	Jean-Philippe Brucker <jean-philippe.brucker@arm.com>,
	"Chintakuntla, Radha" <Radha.Chintakuntla@caviumnetworks.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Jiri Slaby <jslaby@suse.com>, David Airlie <airlied@linux.ie>,
	<ddaney.cavm@gmail.com>, <dri-devel@lists.freedesktop.org>,
	<linux-fbdev@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
	<stable@vger.kernel.org>
Subject: Re: [PATCH] fbcon: warn on invalid cursor blink intervals
References: <1463510464-28124-1-git-send-email-ddaney.cavm@gmail.com> <20160517204912.GA29719@amd> <CACVXFVPdjfFkRFucTQsOHsVFtgm1W0JtOTqjyDzyNbzygghUyg@mail.gmail.com> <alpine.DEB.2.10.1605181519540.8967@laptop> <ed8fa4ca-49e0-3ff4-5499-fc5250dd8ae2@caviumnetworks.com> <alpine.DEB.2.10.1605182252230.12118@laptop> <573DE2D0.1050402@caviumnetworks.com> <alpine.DEB.2.10.1605191708400.15396@laptop> <alpine.DEB.2.10.1605191726030.15478@laptop>
In-Reply-To: <alpine.DEB.2.10.1605191726030.15478@laptop>
Content-Type: text/plain; charset="ISO-8859-1"; format=flowed
Content-Transfer-Encoding: 7bit
Sender: stable-owner@vger.kernel.org
List-ID: <stable.vger.kernel.org>

On 05/19/2016 03:31 PM, Scot Doyle wrote:
> Two systems are locking on boot [1] because ops->cur_blink_jiffies
> is set to zero from vc->vc_cur_blink_ms.
>
> Ignore such invalid intervals and log a warning.
>
> [1] https://bugs.launchpad.net/bugs/1574814
>
> Suggested-by: David Daney <david.daney@cavium.com>
> Signed-off-by: Scot Doyle <lkml14@scotdoyle.com>
> Cc: <stable@vger.kernel.org> [v4.2]

This seems better. I didn't test it, but...

Acked-by: David Daney <david.daney@cavium.com>


> ---
>   drivers/video/console/fbcon.c | 14 ++++++++++++--
>   1 file changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c
> index 6e92917..fad5b89 100644
> --- a/drivers/video/console/fbcon.c
> +++ b/drivers/video/console/fbcon.c
> @@ -1095,7 +1095,13 @@ static void fbcon_init(struct vc_data *vc, int init)
>   		con_copy_unimap(vc, svc);
>
>   	ops = info->fbcon_par;
> -	ops->cur_blink_jiffies = msecs_to_jiffies(vc->vc_cur_blink_ms);
> +
> +	if (vc->vc_cur_blink_ms >= 50)
> +		ops->cur_blink_jiffies =
> +		    msecs_to_jiffies(vc->vc_cur_blink_ms);
> +	else
> +		WARN_ONCE(1, "blink interval < 50 ms");
> +
>   	p->con_rotate = initial_rotation;
>   	set_blitting_type(vc, info);
>
> @@ -1309,7 +1315,11 @@ static void fbcon_cursor(struct vc_data *vc, int mode)
>   	int y;
>    	int c = scr_readw((u16 *) vc->vc_pos);
>
> -	ops->cur_blink_jiffies = msecs_to_jiffies(vc->vc_cur_blink_ms);
> +	if (vc->vc_cur_blink_ms >= 50)
> +		ops->cur_blink_jiffies =
> +		    msecs_to_jiffies(vc->vc_cur_blink_ms);
> +	else
> +		WARN_ONCE(1, "blink interval < 50 ms");
>
>   	if (fbcon_is_inactive(vc, info) || vc->vc_deccm != 1)
>   		return;
>