From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:51688 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752472AbcGYA3L (ORCPT ); Sun, 24 Jul 2016 20:29:11 -0400 Subject: Patch "tty: vt: Fix soft lockup in fbcon cursor blink timer." has been added to the 3.14-stable tree To: david.daney@cavium.com, gregkh@linuxfoundation.org, hmh@hmh.eng.br, lkml14@scotdoyle.com, ming.lei@canonical.com, pavel@ucw.cz Cc: , From: Date: Sun, 24 Jul 2016 17:29:22 -0700 Message-ID: <146940656223217@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled tty: vt: Fix soft lockup in fbcon cursor blink timer. to the 3.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: tty-vt-fix-soft-lockup-in-fbcon-cursor-blink-timer.patch and it can be found in the queue-3.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 1b45996d2ebf9680ccd0db875fc668aa025f40fd Mon Sep 17 00:00:00 2001 From: David Daney Date: Tue, 17 May 2016 11:41:04 -0700 Subject: tty: vt: Fix soft lockup in fbcon cursor blink timer. From: David Daney commit 1b45996d2ebf9680ccd0db875fc668aa025f40fd upstream. We are getting somewhat random soft lockups with this signature: [ 86.992215] [] el1_irq+0xa0/0x10c [ 86.997082] [] cursor_timer_handler+0x30/0x54 [ 87.002991] [] call_timer_fn+0x54/0x1a8 [ 87.008378] [] run_timer_softirq+0x1c4/0x2bc [ 87.014200] [] __do_softirq+0x114/0x344 [ 87.019590] [] irq_exit+0x74/0x98 [ 87.024458] [] __handle_domain_irq+0x98/0xfc [ 87.030278] [] gic_handle_irq+0x94/0x190 This is caused by the vt visual_init() function calling into fbcon_init() with a vc_cur_blink_ms value of zero. This is a transient condition, as it is later set to a non-zero value. But, if the timer happens to expire while the blink rate is zero, it goes into an endless loop, and we get soft lockup. The fix is to initialize vc_cur_blink_ms before calling the con_init() function. Signed-off-by: David Daney Acked-by: Pavel Machek Tested-by: Ming Lei Acked-by: Scot Doyle Tested-by: Henrique de Moraes Holschuh Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman --- drivers/tty/vt/vt.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -742,6 +742,7 @@ static void visual_init(struct vc_data * vc->vc_complement_mask = 0; vc->vc_can_do_color = 0; vc->vc_panic_force_write = false; + vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS; vc->vc_sw->con_init(vc, init); if (!vc->vc_complement_mask) vc->vc_complement_mask = vc->vc_can_do_color ? 0x7700 : 0x0800; Patches currently in stable-queue which might be from david.daney@cavium.com are queue-3.14/tty-vt-fix-soft-lockup-in-fbcon-cursor-blink-timer.patch