linux-kernel - Re: [PATCH v2 2/3] fbcon: use the cursor blink interval provided by vt

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20150519214011.GA27047@ulmo.nvidia.com>
Date:	Tue, 19 May 2015 23:40:12 +0200
From:	Thierry Reding <thierry.reding@...il.com>
To:	Kevin Hilman <khilman@...nel.org>
Cc:	Scot Doyle <lkml14@...tdoyle.com>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	Tomi Valkeinen <tomi.valkeinen@...com>,
	Michael Kerrisk <mtk.manpages@...il.com>,
	Jiri Slaby <jslaby@...e.cz>,
	Jean-Christophe Plagniol-Villard <plagnioj@...osoft.com>,
	Pavel Machek <pavel@....cz>,
	Geert Uytterhoeven <geert@...ux-m68k.org>,
	lkml <linux-kernel@...r.kernel.org>, linux-fbdev@...r.kernel.org,
	linux-man@...r.kernel.org, linux-api@...r.kernel.org,
	Tyler Baker <tyler.baker@...aro.org>,
	Olof Johansson <olof@...om.net>,
	Daniel Stone <daniel@...ishbar.org>,
	Arnd Bergmann <arnd@...db.de>
Subject: Re: [PATCH v2 2/3] fbcon: use the cursor blink interval provided by
 vt

On Tue, May 19, 2015 at 02:15:41PM -0700, Kevin Hilman wrote:
> On Thu, Mar 26, 2015 at 6:56 AM, Scot Doyle <lkml14@...tdoyle.com> wrote:
> > vt now provides a cursor blink interval via vc_data. Use this
> > interval instead of the currently hardcoded 200 msecs. Store it in
> > fbcon_ops to avoid locking the console in cursor_timer_handler().
> >
> > Signed-off-by: Scot Doyle <lkml14@...tdoyle.com>
> > Acked-by: Pavel Machek <pavel@....cz>
> 
> This patch hit next-20150519 in the form of commit 27a4c827c34a
> (fbcon: use the cursor blink interval provided by vt) and has caused
> boot failure on a handful of ARM platforms when booting a MMC root
> filesystem.  This error was spotted by the kernelci.org bot on
> exynos5800-peach-pi[1] and Thierry and Daniel (Cc'd) have seen it on
> some tegra platforms too.
> 
> Thierry spotted this commit as a potential cause, and both Daniel and
> I have reverted and boot tested on exynos5 and tegra respectively and
> the boot panics disappear.

FWIW, if I apply the below on top of next-20150519 things seem to be
back to normal as well:

diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c
index 05b1d1a71ef9..658c34bb9076 100644
--- a/drivers/video/console/fbcon.c
+++ b/drivers/video/console/fbcon.c
@@ -1310,8 +1310,9 @@ static void fbcon_cursor(struct vc_data *vc, int mode)
                return;
 
        ops->cur_blink_jiffies = msecs_to_jiffies(vc->vc_cur_blink_ms);
-       fbcon_del_cursor_timer(info);
-       if (!(vc->vc_cursor_type & 0x10))
+       if (vc->vc_cursor_type & 0x10)
+               fbcon_del_cursor_timer(info);
+       else
                fbcon_add_cursor_timer(info);
 
        ops->cursor_flash = (mode == CM_ERASE) ? 0 : 1;

Content of type "application/pgp-signature" skipped