| Message ID | 1464065754-19883-1-git-send-email-ming.lei@canonical.com |
|---|---|
| State | New |
| Headers | show |
On Tue, May 24, 2016 at 12:55:54PM +0800, Ming Lei wrote: > From: David Daney <david.daney@cavium.com> > > BugLink: http://bugs.launchpad.net/bugs/1574814 > > 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. > > Tested-by: Ming Lei <ming.lei@canonical.com> > Acked-by: Pavel Machek <pavel@ucw.cz> > Acked-by: Scot Doyle <lkml14@scotdoyle.com> > Signed-off-by: David Daney <david.daney@cavium.com> > Cc: stable@vger.kernel.org When you cherry-pick onto Xenial can you also include the -x flag to append the commit hash? --chris > --- > drivers/tty/vt/vt.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c > index 4af9a8f..d80f4ec 100644 > --- a/drivers/tty/vt/vt.c > +++ b/drivers/tty/vt/vt.c > @@ -761,6 +761,7 @@ static void visual_init(struct vc_data *vc, int num, int init) > 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; > -- > 1.9.1 > > > -- > kernel-team mailing list > kernel-team@lists.ubuntu.com > https://lists.ubuntu.com/mailman/listinfo/kernel-team
Needs to be an 'UBUNTU: SAUCE:' patch when applied.
On Tue, May 24, 2016 at 7:11 PM, Chris J Arges <chris.j.arges@canonical.com> wrote: > On Tue, May 24, 2016 at 12:55:54PM +0800, Ming Lei wrote: >> From: David Daney <david.daney@cavium.com> >> >> BugLink: http://bugs.launchpad.net/bugs/1574814 >> >> 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. >> >> Tested-by: Ming Lei <ming.lei@canonical.com> >> Acked-by: Pavel Machek <pavel@ucw.cz> >> Acked-by: Scot Doyle <lkml14@scotdoyle.com> >> Signed-off-by: David Daney <david.daney@cavium.com> >> Cc: stable@vger.kernel.org > > When you cherry-pick onto Xenial can you also include the -x flag to append the > commit hash? This patch doesn't land linus tree yet, and it does block di installer & mass enablement, so hope it can land xenial first. Thanks, > --chris > >> --- >> drivers/tty/vt/vt.c | 1 + >> 1 file changed, 1 insertion(+) >> >> diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c >> index 4af9a8f..d80f4ec 100644 >> --- a/drivers/tty/vt/vt.c >> +++ b/drivers/tty/vt/vt.c >> @@ -761,6 +761,7 @@ static void visual_init(struct vc_data *vc, int num, int init) >> 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; >> -- >> 1.9.1 >> >> >> -- >> kernel-team mailing list >> kernel-team@lists.ubuntu.com >> https://lists.ubuntu.com/mailman/listinfo/kernel-team
Applied this as:
UBUNTU: SAUCE: tty: vt: Fix soft lockup in fbcon cursor blink timer.
and inserted LKML reference:
Reference: https://lkml.org/lkml/2016/5/17/455
-Kamal
On Tue, May 24, 2016 at 12:55:54PM +0800, Ming Lei wrote:
> From: David Daney <david.daney@cavium.com>
>
> BugLink: http://bugs.launchpad.net/bugs/1574814
>
> 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.
>
> Tested-by: Ming Lei <ming.lei@canonical.com>
> Acked-by: Pavel Machek <pavel@ucw.cz>
> Acked-by: Scot Doyle <lkml14@scotdoyle.com>
> Signed-off-by: David Daney <david.daney@cavium.com>
> Cc: stable@vger.kernel.org
> ---
> drivers/tty/vt/vt.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
> index 4af9a8f..d80f4ec 100644
> --- a/drivers/tty/vt/vt.c
> +++ b/drivers/tty/vt/vt.c
> @@ -761,6 +761,7 @@ static void visual_init(struct vc_data *vc, int num, int init)
> 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;
> --
> 1.9.1
>
>
> --
> kernel-team mailing list
> kernel-team@lists.ubuntu.com
> https://lists.ubuntu.com/mailman/listinfo/kernel-team
diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c index 4af9a8f..d80f4ec 100644 --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -761,6 +761,7 @@ static void visual_init(struct vc_data *vc, int num, int init) 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;