* Patch "tty: vt: Fix soft lockup in fbcon cursor blink timer." has been added to the 3.14-stable tree
@ 2016-07-25 0:29 gregkh
2016-07-25 14:02 ` Scot Doyle
0 siblings, 1 reply; 3+ messages in thread
From: gregkh @ 2016-07-25 0:29 UTC (permalink / raw)
To: david.daney, gregkh, hmh, lkml14, ming.lei, pavel; +Cc: stable, stable-commits
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 <stable@vger.kernel.org> know about it.
>From 1b45996d2ebf9680ccd0db875fc668aa025f40fd Mon Sep 17 00:00:00 2001
From: David Daney <david.daney@cavium.com>
Date: Tue, 17 May 2016 11:41:04 -0700
Subject: tty: vt: Fix soft lockup in fbcon cursor blink timer.
From: David Daney <david.daney@cavium.com>
commit 1b45996d2ebf9680ccd0db875fc668aa025f40fd upstream.
We are getting somewhat random soft lockups with this signature:
[ 86.992215] [<fffffc00080935e0>] el1_irq+0xa0/0x10c
[ 86.997082] [<fffffc000841822c>] cursor_timer_handler+0x30/0x54
[ 87.002991] [<fffffc000810ec44>] call_timer_fn+0x54/0x1a8
[ 87.008378] [<fffffc000810ef88>] run_timer_softirq+0x1c4/0x2bc
[ 87.014200] [<fffffc000809077c>] __do_softirq+0x114/0x344
[ 87.019590] [<fffffc00080af45c>] irq_exit+0x74/0x98
[ 87.024458] [<fffffc00080fac20>] __handle_domain_irq+0x98/0xfc
[ 87.030278] [<fffffc000809056c>] 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 <david.daney@cavium.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Tested-by: Ming Lei <ming.lei@canonical.com>
Acked-by: Scot Doyle <lkml14@scotdoyle.com>
Tested-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
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
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: Patch "tty: vt: Fix soft lockup in fbcon cursor blink timer." has been added to the 3.14-stable tree
2016-07-25 0:29 Patch "tty: vt: Fix soft lockup in fbcon cursor blink timer." has been added to the 3.14-stable tree gregkh
@ 2016-07-25 14:02 ` Scot Doyle
2016-07-25 14:56 ` Greg KH
0 siblings, 1 reply; 3+ messages in thread
From: Scot Doyle @ 2016-07-25 14:02 UTC (permalink / raw)
To: stable, gregkh; +Cc: david.daney, hmh, lkml14, ming.lei, pavel
On Sun, 24 Jul 2016, gregkh@linuxfoundation.org wrote:
> 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 <stable@vger.kernel.org> know about it.
>
>
> >From 1b45996d2ebf9680ccd0db875fc668aa025f40fd Mon Sep 17 00:00:00 2001
> From: David Daney <david.daney@cavium.com>
> Date: Tue, 17 May 2016 11:41:04 -0700
> Subject: tty: vt: Fix soft lockup in fbcon cursor blink timer.
>
> From: David Daney <david.daney@cavium.com>
>
> commit 1b45996d2ebf9680ccd0db875fc668aa025f40fd upstream.
>
> We are getting somewhat random soft lockups with this signature:
>
> [ 86.992215] [<fffffc00080935e0>] el1_irq+0xa0/0x10c
> [ 86.997082] [<fffffc000841822c>] cursor_timer_handler+0x30/0x54
> [ 87.002991] [<fffffc000810ec44>] call_timer_fn+0x54/0x1a8
> [ 87.008378] [<fffffc000810ef88>] run_timer_softirq+0x1c4/0x2bc
> [ 87.014200] [<fffffc000809077c>] __do_softirq+0x114/0x344
> [ 87.019590] [<fffffc00080af45c>] irq_exit+0x74/0x98
> [ 87.024458] [<fffffc00080fac20>] __handle_domain_irq+0x98/0xfc
> [ 87.030278] [<fffffc000809056c>] 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 <david.daney@cavium.com>
> Acked-by: Pavel Machek <pavel@ucw.cz>
> Tested-by: Ming Lei <ming.lei@canonical.com>
> Acked-by: Scot Doyle <lkml14@scotdoyle.com>
> Tested-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>
> ---
> 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
>
Hi Greg,
This patch is only necessary for >= 4.2 kernels.
Thanks,
Scot
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: Patch "tty: vt: Fix soft lockup in fbcon cursor blink timer." has been added to the 3.14-stable tree
2016-07-25 14:02 ` Scot Doyle
@ 2016-07-25 14:56 ` Greg KH
0 siblings, 0 replies; 3+ messages in thread
From: Greg KH @ 2016-07-25 14:56 UTC (permalink / raw)
To: Scot Doyle; +Cc: stable, david.daney, hmh, ming.lei, pavel
On Mon, Jul 25, 2016 at 09:02:28AM -0500, Scot Doyle wrote:
> On Sun, 24 Jul 2016, gregkh@linuxfoundation.org wrote:
> > 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 <stable@vger.kernel.org> know about it.
> >
> >
> > >From 1b45996d2ebf9680ccd0db875fc668aa025f40fd Mon Sep 17 00:00:00 2001
> > From: David Daney <david.daney@cavium.com>
> > Date: Tue, 17 May 2016 11:41:04 -0700
> > Subject: tty: vt: Fix soft lockup in fbcon cursor blink timer.
> >
> > From: David Daney <david.daney@cavium.com>
> >
> > commit 1b45996d2ebf9680ccd0db875fc668aa025f40fd upstream.
> >
> > We are getting somewhat random soft lockups with this signature:
> >
> > [ 86.992215] [<fffffc00080935e0>] el1_irq+0xa0/0x10c
> > [ 86.997082] [<fffffc000841822c>] cursor_timer_handler+0x30/0x54
> > [ 87.002991] [<fffffc000810ec44>] call_timer_fn+0x54/0x1a8
> > [ 87.008378] [<fffffc000810ef88>] run_timer_softirq+0x1c4/0x2bc
> > [ 87.014200] [<fffffc000809077c>] __do_softirq+0x114/0x344
> > [ 87.019590] [<fffffc00080af45c>] irq_exit+0x74/0x98
> > [ 87.024458] [<fffffc00080fac20>] __handle_domain_irq+0x98/0xfc
> > [ 87.030278] [<fffffc000809056c>] 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 <david.daney@cavium.com>
> > Acked-by: Pavel Machek <pavel@ucw.cz>
> > Tested-by: Ming Lei <ming.lei@canonical.com>
> > Acked-by: Scot Doyle <lkml14@scotdoyle.com>
> > Tested-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
> > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> >
> > ---
> > 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
> >
>
> Hi Greg,
>
> This patch is only necessary for >= 4.2 kernels.
Yeah, that was obvious when it broke the 3.14 build, so I removed it
from the queue yesterday :)
thanks,
greg k-h
^ permalink raw reply [flat|nested] 3+ messages in thread
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2016-07-25 0:29 Patch "tty: vt: Fix soft lockup in fbcon cursor blink timer." has been added to the 3.14-stable tree gregkh
2016-07-25 14:02 ` Scot Doyle
2016-07-25 14:56 ` Greg KH
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