2015-06-30 11:57:16

by Michal Hocko

[permalink] [raw]
Subject: WARNING: CPU: 0 PID: 3634 at drivers/gpu/drm/drm_irq.c:1141 drm_wait_one_vblank

Hi,
I am getting the following warning when I switch to the text console
from X. I do not know when this has started because I have noticed
that only now (in 4.1 kernel). I can try some older kernels if this is
useful.

I have tried to instrument drm_wait_one_vblank and dump drm_vblank_count
before the wait_event and the value when it returns (see the diff below)
and it seems to be increasing with new switching to the text console:
$ dmesg | grep XXX
[ 6.531908] XXX: last:36
[ 6.545852] XXX: drm_vblank_count:37
[ 9.038658] XXX: last:186
[ 9.051332] XXX: drm_vblank_count:187
[ 9.051424] XXX: last:187
[ 9.068036] XXX: drm_vblank_count:188
[ 16.962193] XXX: last:660
[ 16.968683] XXX: drm_vblank_count:661
[ 30.592874] XXX: last:1476
[ 30.598656] XXX: drm_vblank_count:1477
[ 30.598768] XXX: last:1477
[ 30.615339] XXX: drm_vblank_count:1478
[ 37.313338] XXX: last:1879
[ 37.330102] XXX: drm_vblank_count:1880
[ 39.726809] XXX: last:2023
[ 39.735265] XXX: drm_vblank_count:2024
[ 39.735375] XXX: last:2024
[ 39.752094] XXX: drm_vblank_count:2025
[ 60.842401] XXX: last:3287
[ 60.848437] XXX: drm_vblank_count:3288
[ 62.149546] XXX: last:3365
[ 62.151277] XXX: drm_vblank_count:3366
[ 62.151411] XXX: last:3366
[ 62.249376] XXX: drm_vblank_count:3366
[ 92.198305] XXX: last:5160
[ 92.297091] XXX: drm_vblank_count:5160
[ 93.822331] XXX: last:5253
[ 93.922153] XXX: drm_vblank_count:5253
[ 93.922424] XXX: last:5254
[ 94.022213] XXX: drm_vblank_count:5254
[ 100.877802] XXX: last:5665
[ 100.974740] XXX: drm_vblank_count:5665

I am sorry about the lack of information in this report but I am really
not sure what might be helpful. I can only tell that I haven't observed
anything wrong going on after the warning so it might be harmless.

Let me know what kind of information might be helpful.

[ 7322.444556] ------------[ cut here ]------------
[ 7322.444569] WARNING: CPU: 0 PID: 3634 at drivers/gpu/drm/drm_irq.c:1141 drm_wait_one_vblank+0x144/0x16f [drm]()
[ 7322.444570] vblank wait timed out on crtc 0
[ 7322.444586] Modules linked in: i915 fbcon cfbfillrect bitblit softcursor cfbimgblt font i2c_algo_bit cfbcopyarea drm_kms_helper drm fb fbdev binfmt_misc snd_hda_codec_hdmi uvcvideo videobuf2_vmalloc videobuf2_memops snd_hda_codec_idt i2c_i801 snd_hda_codec_generic snd_hda_intel snd_hda_controller videobuf2_core arc4 snd_hda_codec snd_hda_core snd_pcm_oss v4l2_common snd_mixer_oss videodev iwldvm media i2c_core mac80211 video iwlwifi backlight snd_pcm sdhci_pci sdhci mmc_core cfg80211 snd_timer snd
[ 7322.444588] CPU: 0 PID: 3634 Comm: Xorg Not tainted 4.1.0 #587
[ 7322.444589] Hardware name: Dell Inc. Latitude E6320/09PHH9, BIOS A08 10/18/2011
[ 7322.444591] 0000000000000009 ffff8800c5bb7888 ffffffff8151b709 0000000080000000
[ 7322.444592] ffff8800c5bb78d8 ffff8800c5bb78c8 ffffffff8104550a ffff8800c5bb7958
[ 7322.444593] ffffffffa02d414e 0000000000000000 0000000000000000 ffff8800c58d7000
[ 7322.444594] Call Trace:
[ 7322.444599] [<ffffffff8151b709>] dump_stack+0x4f/0x7b
[ 7322.444601] [<ffffffff8104550a>] warn_slowpath_common+0xa1/0xbb
[ 7322.444608] [<ffffffffa02d414e>] ? drm_wait_one_vblank+0x144/0x16f [drm]
[ 7322.444609] [<ffffffff8104556a>] warn_slowpath_fmt+0x46/0x48
[ 7322.444611] [<ffffffff81075b7d>] ? finish_wait+0x59/0x62
[ 7322.444617] [<ffffffffa02d414e>] drm_wait_one_vblank+0x144/0x16f [drm]
[ 7322.444618] [<ffffffff81075c9d>] ? wait_woken+0x76/0x76
[ 7322.444624] [<ffffffffa02d4196>] drm_crtc_wait_one_vblank+0x1d/0x21 [drm]
[ 7322.444628] [<ffffffffa0331baa>] drm_plane_helper_commit+0x1b3/0x240 [drm_kms_helper]
[ 7322.444631] [<ffffffffa0331cfe>] drm_plane_helper_update+0xc7/0xd6 [drm_kms_helper]
[ 7322.444652] [<ffffffffa03cd9a5>] intel_crtc_set_config+0x95e/0xc4f [i915]
[ 7322.444661] [<ffffffffa02db020>] drm_mode_set_config_internal+0x5c/0xe8 [drm]
[ 7322.444666] [<ffffffffa0338ae3>] drm_fb_helper_pan_display+0xa2/0xd8 [drm_kms_helper]
[ 7322.444668] [<ffffffffa02be312>] fb_pan_display+0xee/0x131 [fb]
[ 7322.444670] [<ffffffffa0353254>] bit_update_start+0x20/0x43 [bitblit]
[ 7322.444672] [<ffffffffa035fa24>] fbcon_switch+0x3b7/0x438 [fbcon]
[ 7322.444674] [<ffffffff812f7f0d>] redraw_screen+0x112/0x1e3
[ 7322.444676] [<ffffffff812f0711>] complete_change_console+0x3e/0xc7
[ 7322.444678] [<ffffffff812f1684>] vt_ioctl+0xeea/0x117f
[ 7322.444680] [<ffffffff812e7538>] tty_ioctl+0xa01/0xa74
[ 7322.444682] [<ffffffff81065154>] ? preempt_count_sub+0xc6/0xd3
[ 7322.444684] [<ffffffff81156204>] do_vfs_ioctl+0x377/0x425
[ 7322.444685] [<ffffffff8115e2a9>] ? __fget+0x70/0x7b
[ 7322.444686] [<ffffffff811562f6>] SyS_ioctl+0x44/0x63
[ 7322.444688] [<ffffffff81520197>] system_call_fastpath+0x12/0x6a
[ 7322.444689] ---[ end trace 9d3b554e7f553db3 ]---
[ 7326.066994] ------------[ cut here ]------------

Debugging patch
--
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index af9662e58272..446f4ce02a9d 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -1126,17 +1126,19 @@ EXPORT_SYMBOL(drm_crtc_vblank_put);
void drm_wait_one_vblank(struct drm_device *dev, int crtc)
{
int ret;
- u32 last;
+ u32 last, l;

ret = drm_vblank_get(dev, crtc);
if (WARN(ret, "vblank not available on crtc %i, ret=%i\n", crtc, ret))
return;

last = drm_vblank_count(dev, crtc);
+ pr_info("XXX: last:%u\n", last);

ret = wait_event_timeout(dev->vblank[crtc].queue,
- last != drm_vblank_count(dev, crtc),
+ last != (l = drm_vblank_count(dev, crtc)),
msecs_to_jiffies(100));
+ pr_info("XXX: drm_vblank_count:%u\n", l);

WARN(ret == 0, "vblank wait timed out on crtc %i\n", crtc);

--
Michal Hocko
SUSE Labs


2015-06-30 14:31:14

by Daniel Vetter

[permalink] [raw]
Subject: Re: WARNING: CPU: 0 PID: 3634 at drivers/gpu/drm/drm_irq.c:1141 drm_wait_one_vblank

On Tue, Jun 30, 2015 at 01:57:07PM +0200, Michal Hocko wrote:
> Hi,
> I am getting the following warning when I switch to the text console
> from X. I do not know when this has started because I have noticed
> that only now (in 4.1 kernel). I can try some older kernels if this is
> useful.
>
> I have tried to instrument drm_wait_one_vblank and dump drm_vblank_count
> before the wait_event and the value when it returns (see the diff below)
> and it seems to be increasing with new switching to the text console:
> $ dmesg | grep XXX
> [ 6.531908] XXX: last:36
> [ 6.545852] XXX: drm_vblank_count:37
> [ 9.038658] XXX: last:186
> [ 9.051332] XXX: drm_vblank_count:187
> [ 9.051424] XXX: last:187
> [ 9.068036] XXX: drm_vblank_count:188
> [ 16.962193] XXX: last:660
> [ 16.968683] XXX: drm_vblank_count:661
> [ 30.592874] XXX: last:1476
> [ 30.598656] XXX: drm_vblank_count:1477
> [ 30.598768] XXX: last:1477
> [ 30.615339] XXX: drm_vblank_count:1478
> [ 37.313338] XXX: last:1879
> [ 37.330102] XXX: drm_vblank_count:1880
> [ 39.726809] XXX: last:2023
> [ 39.735265] XXX: drm_vblank_count:2024
> [ 39.735375] XXX: last:2024
> [ 39.752094] XXX: drm_vblank_count:2025
> [ 60.842401] XXX: last:3287
> [ 60.848437] XXX: drm_vblank_count:3288
> [ 62.149546] XXX: last:3365
> [ 62.151277] XXX: drm_vblank_count:3366
> [ 62.151411] XXX: last:3366
> [ 62.249376] XXX: drm_vblank_count:3366
> [ 92.198305] XXX: last:5160
> [ 92.297091] XXX: drm_vblank_count:5160
> [ 93.822331] XXX: last:5253
> [ 93.922153] XXX: drm_vblank_count:5253
> [ 93.922424] XXX: last:5254
> [ 94.022213] XXX: drm_vblank_count:5254
> [ 100.877802] XXX: last:5665
> [ 100.974740] XXX: drm_vblank_count:5665
>
> I am sorry about the lack of information in this report but I am really
> not sure what might be helpful. I can only tell that I haven't observed
> anything wrong going on after the warning so it might be harmless.
>
> Let me know what kind of information might be helpful.

Looks like the vblank is actually running, just the wakeup somehow doesn't
happen in time. What machine is this (lspci -nn)? Also please boot with
drm.debug=0xe and grab dmesg after this happens for the first time.
logfile will be large, you might need to increase the buffer size with
log_buf_len or grab
it from the hd.

Also what happens when you increase the timeout to 1000 (just to make sure
it's not just a silly delay somewhere). Also have you any special features
like psr, fbc or something similar enabled?

Really surprising since we have all the checks in place that should ensure
that the vblank stuff is indeed up&running.
-Daniel

>
> [ 7322.444556] ------------[ cut here ]------------
> [ 7322.444569] WARNING: CPU: 0 PID: 3634 at drivers/gpu/drm/drm_irq.c:1141 drm_wait_one_vblank+0x144/0x16f [drm]()
> [ 7322.444570] vblank wait timed out on crtc 0
> [ 7322.444586] Modules linked in: i915 fbcon cfbfillrect bitblit softcursor cfbimgblt font i2c_algo_bit cfbcopyarea drm_kms_helper drm fb fbdev binfmt_misc snd_hda_codec_hdmi uvcvideo videobuf2_vmalloc videobuf2_memops snd_hda_codec_idt i2c_i801 snd_hda_codec_generic snd_hda_intel snd_hda_controller videobuf2_core arc4 snd_hda_codec snd_hda_core snd_pcm_oss v4l2_common snd_mixer_oss videodev iwldvm media i2c_core mac80211 video iwlwifi backlight snd_pcm sdhci_pci sdhci mmc_core cfg80211 snd_timer snd
> [ 7322.444588] CPU: 0 PID: 3634 Comm: Xorg Not tainted 4.1.0 #587
> [ 7322.444589] Hardware name: Dell Inc. Latitude E6320/09PHH9, BIOS A08 10/18/2011
> [ 7322.444591] 0000000000000009 ffff8800c5bb7888 ffffffff8151b709 0000000080000000
> [ 7322.444592] ffff8800c5bb78d8 ffff8800c5bb78c8 ffffffff8104550a ffff8800c5bb7958
> [ 7322.444593] ffffffffa02d414e 0000000000000000 0000000000000000 ffff8800c58d7000
> [ 7322.444594] Call Trace:
> [ 7322.444599] [<ffffffff8151b709>] dump_stack+0x4f/0x7b
> [ 7322.444601] [<ffffffff8104550a>] warn_slowpath_common+0xa1/0xbb
> [ 7322.444608] [<ffffffffa02d414e>] ? drm_wait_one_vblank+0x144/0x16f [drm]
> [ 7322.444609] [<ffffffff8104556a>] warn_slowpath_fmt+0x46/0x48
> [ 7322.444611] [<ffffffff81075b7d>] ? finish_wait+0x59/0x62
> [ 7322.444617] [<ffffffffa02d414e>] drm_wait_one_vblank+0x144/0x16f [drm]
> [ 7322.444618] [<ffffffff81075c9d>] ? wait_woken+0x76/0x76
> [ 7322.444624] [<ffffffffa02d4196>] drm_crtc_wait_one_vblank+0x1d/0x21 [drm]
> [ 7322.444628] [<ffffffffa0331baa>] drm_plane_helper_commit+0x1b3/0x240 [drm_kms_helper]
> [ 7322.444631] [<ffffffffa0331cfe>] drm_plane_helper_update+0xc7/0xd6 [drm_kms_helper]
> [ 7322.444652] [<ffffffffa03cd9a5>] intel_crtc_set_config+0x95e/0xc4f [i915]
> [ 7322.444661] [<ffffffffa02db020>] drm_mode_set_config_internal+0x5c/0xe8 [drm]
> [ 7322.444666] [<ffffffffa0338ae3>] drm_fb_helper_pan_display+0xa2/0xd8 [drm_kms_helper]
> [ 7322.444668] [<ffffffffa02be312>] fb_pan_display+0xee/0x131 [fb]
> [ 7322.444670] [<ffffffffa0353254>] bit_update_start+0x20/0x43 [bitblit]
> [ 7322.444672] [<ffffffffa035fa24>] fbcon_switch+0x3b7/0x438 [fbcon]
> [ 7322.444674] [<ffffffff812f7f0d>] redraw_screen+0x112/0x1e3
> [ 7322.444676] [<ffffffff812f0711>] complete_change_console+0x3e/0xc7
> [ 7322.444678] [<ffffffff812f1684>] vt_ioctl+0xeea/0x117f
> [ 7322.444680] [<ffffffff812e7538>] tty_ioctl+0xa01/0xa74
> [ 7322.444682] [<ffffffff81065154>] ? preempt_count_sub+0xc6/0xd3
> [ 7322.444684] [<ffffffff81156204>] do_vfs_ioctl+0x377/0x425
> [ 7322.444685] [<ffffffff8115e2a9>] ? __fget+0x70/0x7b
> [ 7322.444686] [<ffffffff811562f6>] SyS_ioctl+0x44/0x63
> [ 7322.444688] [<ffffffff81520197>] system_call_fastpath+0x12/0x6a
> [ 7322.444689] ---[ end trace 9d3b554e7f553db3 ]---
> [ 7326.066994] ------------[ cut here ]------------
>
> Debugging patch
> --
> diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
> index af9662e58272..446f4ce02a9d 100644
> --- a/drivers/gpu/drm/drm_irq.c
> +++ b/drivers/gpu/drm/drm_irq.c
> @@ -1126,17 +1126,19 @@ EXPORT_SYMBOL(drm_crtc_vblank_put);
> void drm_wait_one_vblank(struct drm_device *dev, int crtc)
> {
> int ret;
> - u32 last;
> + u32 last, l;
>
> ret = drm_vblank_get(dev, crtc);
> if (WARN(ret, "vblank not available on crtc %i, ret=%i\n", crtc, ret))
> return;
>
> last = drm_vblank_count(dev, crtc);
> + pr_info("XXX: last:%u\n", last);
>
> ret = wait_event_timeout(dev->vblank[crtc].queue,
> - last != drm_vblank_count(dev, crtc),
> + last != (l = drm_vblank_count(dev, crtc)),
> msecs_to_jiffies(100));
> + pr_info("XXX: drm_vblank_count:%u\n", l);
>
> WARN(ret == 0, "vblank wait timed out on crtc %i\n", crtc);
>
> --
> Michal Hocko
> SUSE Labs

--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

2015-06-30 16:07:55

by Michal Hocko

[permalink] [raw]
Subject: Re: WARNING: CPU: 0 PID: 3634 at drivers/gpu/drm/drm_irq.c:1141 drm_wait_one_vblank

On Tue 30-06-15 16:32:49, Daniel Vetter wrote:
[...]
> Looks like the vblank is actually running, just the wakeup somehow doesn't
> happen in time. What machine is this (lspci -nn)?

00:00.0 Host bridge [0600]: Intel Corporation 2nd Generation Core Processor Family DRAM Controller [8086:0104] (rev 09)
00:02.0 VGA compatible controller [0300]: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller [8086:0126] (rev 09)
00:16.0 Communication controller [0780]: Intel Corporation 6 Series/C200 Series Chipset Family MEI Controller #1 [8086:1c3a] (rev 04)
00:16.3 Serial controller [0700]: Intel Corporation 6 Series/C200 Series Chipset Family KT Controller [8086:1c3d] (rev 04)
00:19.0 Ethernet controller [0200]: Intel Corporation 82579LM Gigabit Network Connection [8086:1502] (rev 04)
00:1a.0 USB controller [0c03]: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #2 [8086:1c2d] (rev 04)
00:1b.0 Audio device [0403]: Intel Corporation 6 Series/C200 Series Chipset Family High Definition Audio Controller [8086:1c20] (rev 04)
00:1c.0 PCI bridge [0604]: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 1 [8086:1c10] (rev b4)
00:1c.1 PCI bridge [0604]: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 2 [8086:1c12] (rev b4)
00:1c.2 PCI bridge [0604]: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 3 [8086:1c14] (rev b4)
00:1c.3 PCI bridge [0604]: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 4 [8086:1c16] (rev b4)
00:1c.5 PCI bridge [0604]: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 6 [8086:1c1a] (rev b4)
00:1d.0 USB controller [0c03]: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #1 [8086:1c26] (rev 04)
00:1f.0 ISA bridge [0601]: Intel Corporation QM67 Express Chipset Family LPC Controller [8086:1c4f] (rev 04)
00:1f.2 SATA controller [0106]: Intel Corporation 6 Series/C200 Series Chipset Family 6 port SATA AHCI Controller [8086:1c03] (rev 04)
00:1f.3 SMBus [0c05]: Intel Corporation 6 Series/C200 Series Chipset Family SMBus Controller [8086:1c22] (rev 04)
02:00.0 Network controller [0280]: Intel Corporation Centrino Ultimate-N 6300 [8086:422b] (rev 35)
0a:00.0 SD Host controller [0805]: O2 Micro, Inc. OZ600FJ0/OZ900FJ0/OZ600FJS SD/MMC Card Reader Controller [1217:8221] (rev 05)

> Also please boot with
> drm.debug=0xe and grab dmesg after this happens for the first time.
> logfile will be large, you might need to increase the buffer size with
> log_buf_len or grab it from the hd.

See attached.

> Also what happens when you increase the timeout to 1000 (just to make sure
> it's not just a silly delay somewhere).

Still happening even when the timeout was increased to 1000. Curiously
the display is much darker with this change and I cannot make it
brighter by function keys...

> Also have you any special features like psr, fbc or something similar
> enabled?

I am not aware of anything like that. How do I check it?

--
Michal Hocko
SUSE Labs


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2015-06-30 16:57:19

by Daniel Vetter

[permalink] [raw]
Subject: Re: WARNING: CPU: 0 PID: 3634 at drivers/gpu/drm/drm_irq.c:1141 drm_wait_one_vblank

On Tue, Jun 30, 2015 at 06:07:44PM +0200, Michal Hocko wrote:
> On Tue 30-06-15 16:32:49, Daniel Vetter wrote:
> [...]
> > Looks like the vblank is actually running, just the wakeup somehow doesn't
> > happen in time. What machine is this (lspci -nn)?
>
> 00:00.0 Host bridge [0600]: Intel Corporation 2nd Generation Core Processor Family DRAM Controller [8086:0104] (rev 09)
> 00:02.0 VGA compatible controller [0300]: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller [8086:0126] (rev 09)
> 00:16.0 Communication controller [0780]: Intel Corporation 6 Series/C200 Series Chipset Family MEI Controller #1 [8086:1c3a] (rev 04)
> 00:16.3 Serial controller [0700]: Intel Corporation 6 Series/C200 Series Chipset Family KT Controller [8086:1c3d] (rev 04)
> 00:19.0 Ethernet controller [0200]: Intel Corporation 82579LM Gigabit Network Connection [8086:1502] (rev 04)
> 00:1a.0 USB controller [0c03]: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #2 [8086:1c2d] (rev 04)
> 00:1b.0 Audio device [0403]: Intel Corporation 6 Series/C200 Series Chipset Family High Definition Audio Controller [8086:1c20] (rev 04)
> 00:1c.0 PCI bridge [0604]: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 1 [8086:1c10] (rev b4)
> 00:1c.1 PCI bridge [0604]: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 2 [8086:1c12] (rev b4)
> 00:1c.2 PCI bridge [0604]: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 3 [8086:1c14] (rev b4)
> 00:1c.3 PCI bridge [0604]: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 4 [8086:1c16] (rev b4)
> 00:1c.5 PCI bridge [0604]: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 6 [8086:1c1a] (rev b4)
> 00:1d.0 USB controller [0c03]: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #1 [8086:1c26] (rev 04)
> 00:1f.0 ISA bridge [0601]: Intel Corporation QM67 Express Chipset Family LPC Controller [8086:1c4f] (rev 04)
> 00:1f.2 SATA controller [0106]: Intel Corporation 6 Series/C200 Series Chipset Family 6 port SATA AHCI Controller [8086:1c03] (rev 04)
> 00:1f.3 SMBus [0c05]: Intel Corporation 6 Series/C200 Series Chipset Family SMBus Controller [8086:1c22] (rev 04)
> 02:00.0 Network controller [0280]: Intel Corporation Centrino Ultimate-N 6300 [8086:422b] (rev 35)
> 0a:00.0 SD Host controller [0805]: O2 Micro, Inc. OZ600FJ0/OZ900FJ0/OZ600FJS SD/MMC Card Reader Controller [1217:8221] (rev 05)
>
> > Also please boot with
> > drm.debug=0xe and grab dmesg after this happens for the first time.
> > logfile will be large, you might need to increase the buffer size with
> > log_buf_len or grab it from the hd.
>
> See attached.
>
> > Also what happens when you increase the timeout to 1000 (just to make sure
> > it's not just a silly delay somewhere).
>
> Still happening even when the timeout was increased to 1000. Curiously
> the display is much darker with this change and I cannot make it
> brighter by function keys...
>
> > Also have you any special features like psr, fbc or something similar
> > enabled?
>
> I am not aware of anything like that. How do I check it?

I looked at dmesg, nothing out of the ordinary there. Unfortunately also
no hints why the pipe is somehow off when we think it's on. Can you please
test the below patch and grab a new dmesg?

Also it might be time to start bisecting this if you can readily reproduce it.
-Daniel

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index d0f3cbc87474..b8d9314ef459 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -12190,7 +12190,7 @@ static int intel_crtc_set_config(struct drm_mode_set *set)
* flipping, so increasing its cost here shouldn't be a big
* deal).
*/
- if (i915.fastboot && ret == 0)
+ if (ret == 0)
intel_modeset_check_state(set->crtc->dev);
}

--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

2015-06-30 20:13:46

by Michal Hocko

[permalink] [raw]
Subject: Re: WARNING: CPU: 0 PID: 3634 at drivers/gpu/drm/drm_irq.c:1141 drm_wait_one_vblank

On Tue 30-06-15 18:59:29, Daniel Vetter wrote:
[...]
> I looked at dmesg, nothing out of the ordinary there. Unfortunately also
> no hints why the pipe is somehow off when we think it's on. Can you please
> test the below patch and grab a new dmesg?

Attached.

> Also it might be time to start bisecting this if you can readily reproduce it.

Yes, I can reproduce it just by switching to the text console. Sometimes
it is the first attempt already but sometimes it takes several attempts.
I will try to go back to 4.0 and bisect it then.

> -Daniel
>
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index d0f3cbc87474..b8d9314ef459 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -12190,7 +12190,7 @@ static int intel_crtc_set_config(struct drm_mode_set *set)
> * flipping, so increasing its cost here shouldn't be a big
> * deal).
> */
> - if (i915.fastboot && ret == 0)
> + if (ret == 0)
> intel_modeset_check_state(set->crtc->dev);
> }
>
> --
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch

--
Michal Hocko
SUSE Labs


Attachments:
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2015-07-01 08:25:33

by Daniel Vetter

[permalink] [raw]
Subject: Re: WARNING: CPU: 0 PID: 3634 at drivers/gpu/drm/drm_irq.c:1141 drm_wait_one_vblank

On Tue, Jun 30, 2015 at 10:13:35PM +0200, Michal Hocko wrote:
> On Tue 30-06-15 18:59:29, Daniel Vetter wrote:
> [...]
> > I looked at dmesg, nothing out of the ordinary there. Unfortunately also
> > no hints why the pipe is somehow off when we think it's on. Can you please
> > test the below patch and grab a new dmesg?
>
> Attached.

I'm still baffled - looking at the code intel_crtc->active should be set,
but somehow the real hw pipe is dead. Or at least we don't get a vblank
irq for it somehow. Confusing.

> > Also it might be time to start bisecting this if you can readily reproduce it.
>
> Yes, I can reproduce it just by switching to the text console. Sometimes
> it is the first attempt already but sometimes it takes several attempts.
> I will try to go back to 4.0 and bisect it then.

Yes please do, since this is a confusing regression I think the bisect
result will be the fastest way forward.
-Daniel
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

2015-07-01 12:12:52

by Michal Hocko

[permalink] [raw]
Subject: Re: WARNING: CPU: 0 PID: 3634 at drivers/gpu/drm/drm_irq.c:1141 drm_wait_one_vblank

On Wed 01-07-15 10:26:39, Daniel Vetter wrote:
> On Tue, Jun 30, 2015 at 10:13:35PM +0200, Michal Hocko wrote:
> > On Tue 30-06-15 18:59:29, Daniel Vetter wrote:
[...]
> > > Also it might be time to start bisecting this if you can readily reproduce it.
> >
> > Yes, I can reproduce it just by switching to the text console. Sometimes
> > it is the first attempt already but sometimes it takes several attempts.
> > I will try to go back to 4.0 and bisect it then.
>
> Yes please do, since this is a confusing regression I think the bisect
> result will be the fastest way forward.

OK, managed to bisect to cf4c7c12258e ("drm/i915: Make all plane
disables use 'update_plane' (v5)") (CC people involved - the thread
starts here: http://marc.info/?l=dri-devel&m=143566543432613&w=2 for
your reference).

I do not see the warning when I revert the commit directly on top of
cf4c7c12258e but I cannot cleanly revert it on top of the current Linus'
tree. Anything more I can give you to help to further debug the issue?

Bisect log is:
git bisect start
# bad: [c517d838eb7d07bbe9507871fab3931deccff539] Linux 4.0-rc1
git bisect bad c517d838eb7d07bbe9507871fab3931deccff539
# good: [bfa76d49576599a4b9f9b7a71f23d73d6dcff735] Linux 3.19
git bisect good bfa76d49576599a4b9f9b7a71f23d73d6dcff735
# good: [02f1f2170d2831b3233e91091c60a66622f29e82] kernel.h: remove ancient __FUNCTION__ hack
git bisect good 02f1f2170d2831b3233e91091c60a66622f29e82
# bad: [796e1c55717e9a6ff5c81b12289ffa1ffd919b6f] Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux
git bisect bad 796e1c55717e9a6ff5c81b12289ffa1ffd919b6f
# good: [9682ec9692e5ac11c6caebd079324e727b19e7ce] Merge tag 'driver-core-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
git bisect good 9682ec9692e5ac11c6caebd079324e727b19e7ce
# good: [a9724125ad014decf008d782e60447c811391326] Merge tag 'tty-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
git bisect good a9724125ad014decf008d782e60447c811391326
# bad: [f43dff0ee00a259f524ce17ba4f8030553c66590] Merge tag 'drm-amdkfd-next-fixes-2015-01-25' of git://people.freedesktop.org/~gabbayo/linux into drm-next
git bisect bad f43dff0ee00a259f524ce17ba4f8030553c66590
# good: [b942c653ae265abbd31032f3b4f5f857e5c7c723] Merge tag 'trace-sh-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
git bisect good b942c653ae265abbd31032f3b4f5f857e5c7c723
# good: [fcf3aac5fc307f0cae429f5844ddc25761662858] drm/i915: remove unused power_well/get_cdclk_freq api
git bisect good fcf3aac5fc307f0cae429f5844ddc25761662858
# bad: [4f4d89af78682f2ed1cf6745794804817f867bba] Merge tag 'drm-amdkfd-next-2015-01-09' of git://people.freedesktop.org/~gabbayo/linux into drm-next
git bisect bad 4f4d89af78682f2ed1cf6745794804817f867bba
# bad: [64387b613a43713d0e03d9d43bfbb1727e8475e1] drm/i915: Protect against leaks in pipe_crc_set_source
git bisect bad 64387b613a43713d0e03d9d43bfbb1727e8475e1
# good: [bfc882b4e30fbc169ecfe3508378623743806f56] drm/i915: Flatten engine init control flow
git bisect good bfc882b4e30fbc169ecfe3508378623743806f56
# good: [2b875c22fa77dfc895d3cf8287a553813d3e64c8] drm/i915: Make intel_plane_state subclass drm_plane_state
git bisect good 2b875c22fa77dfc895d3cf8287a553813d3e64c8
# bad: [15a17aae5f803551981a7acc6a4058b247a7452c] drm/i915: Check mask/bit helper functions
git bisect bad 15a17aae5f803551981a7acc6a4058b247a7452c
# bad: [146d84f0f2707bfe2c67114eeefac30da8584b3b] drm/i915: Fix up seqno -> request merge issues
git bisect bad 146d84f0f2707bfe2c67114eeefac30da8584b3b
# good: [c59cb179aaf444931cf9c547a514e383da3d2526] drm/i915: Consolidate top-level .update_plane() handlers
git bisect good c59cb179aaf444931cf9c547a514e383da3d2526
# bad: [cf4c7c12258ed9367f4fc45238f5f50d2db892c1] drm/i915: Make all plane disables use 'update_plane' (v5)
git bisect bad cf4c7c12258ed9367f4fc45238f5f50d2db892c1
# good: [e614c3c946ae5b50a679d65d2c981615d8ceccab] drm/i915: Ensure state->crtc is non-NULL for plane updates
git bisect good e614c3c946ae5b50a679d65d2c981615d8ceccab
# first bad commit: [cf4c7c12258ed9367f4fc45238f5f50d2db892c1] drm/i915: Make all plane disables use 'update_plane' (v5)
--
Michal Hocko
SUSE Labs

2015-07-01 12:21:12

by Jani Nikula

[permalink] [raw]
Subject: Re: WARNING: CPU: 0 PID: 3634 at drivers/gpu/drm/drm_irq.c:1141 drm_wait_one_vblank


+intel-gfx and Matt

On Wed, 01 Jul 2015, Michal Hocko <[email protected]> wrote:
> On Wed 01-07-15 10:26:39, Daniel Vetter wrote:
>> On Tue, Jun 30, 2015 at 10:13:35PM +0200, Michal Hocko wrote:
>> > On Tue 30-06-15 18:59:29, Daniel Vetter wrote:
> [...]
>> > > Also it might be time to start bisecting this if you can readily reproduce it.
>> >
>> > Yes, I can reproduce it just by switching to the text console. Sometimes
>> > it is the first attempt already but sometimes it takes several attempts.
>> > I will try to go back to 4.0 and bisect it then.
>>
>> Yes please do, since this is a confusing regression I think the bisect
>> result will be the fastest way forward.
>
> OK, managed to bisect to cf4c7c12258e ("drm/i915: Make all plane
> disables use 'update_plane' (v5)") (CC people involved - the thread
> starts here: http://marc.info/?l=dri-devel&m=143566543432613&w=2 for
> your reference).
>
> I do not see the warning when I revert the commit directly on top of
> cf4c7c12258e but I cannot cleanly revert it on top of the current Linus'
> tree. Anything more I can give you to help to further debug the issue?
>
> Bisect log is:
> git bisect start
> # bad: [c517d838eb7d07bbe9507871fab3931deccff539] Linux 4.0-rc1
> git bisect bad c517d838eb7d07bbe9507871fab3931deccff539
> # good: [bfa76d49576599a4b9f9b7a71f23d73d6dcff735] Linux 3.19
> git bisect good bfa76d49576599a4b9f9b7a71f23d73d6dcff735
> # good: [02f1f2170d2831b3233e91091c60a66622f29e82] kernel.h: remove ancient __FUNCTION__ hack
> git bisect good 02f1f2170d2831b3233e91091c60a66622f29e82
> # bad: [796e1c55717e9a6ff5c81b12289ffa1ffd919b6f] Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux
> git bisect bad 796e1c55717e9a6ff5c81b12289ffa1ffd919b6f
> # good: [9682ec9692e5ac11c6caebd079324e727b19e7ce] Merge tag 'driver-core-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
> git bisect good 9682ec9692e5ac11c6caebd079324e727b19e7ce
> # good: [a9724125ad014decf008d782e60447c811391326] Merge tag 'tty-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
> git bisect good a9724125ad014decf008d782e60447c811391326
> # bad: [f43dff0ee00a259f524ce17ba4f8030553c66590] Merge tag 'drm-amdkfd-next-fixes-2015-01-25' of git://people.freedesktop.org/~gabbayo/linux into drm-next
> git bisect bad f43dff0ee00a259f524ce17ba4f8030553c66590
> # good: [b942c653ae265abbd31032f3b4f5f857e5c7c723] Merge tag 'trace-sh-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
> git bisect good b942c653ae265abbd31032f3b4f5f857e5c7c723
> # good: [fcf3aac5fc307f0cae429f5844ddc25761662858] drm/i915: remove unused power_well/get_cdclk_freq api
> git bisect good fcf3aac5fc307f0cae429f5844ddc25761662858
> # bad: [4f4d89af78682f2ed1cf6745794804817f867bba] Merge tag 'drm-amdkfd-next-2015-01-09' of git://people.freedesktop.org/~gabbayo/linux into drm-next
> git bisect bad 4f4d89af78682f2ed1cf6745794804817f867bba
> # bad: [64387b613a43713d0e03d9d43bfbb1727e8475e1] drm/i915: Protect against leaks in pipe_crc_set_source
> git bisect bad 64387b613a43713d0e03d9d43bfbb1727e8475e1
> # good: [bfc882b4e30fbc169ecfe3508378623743806f56] drm/i915: Flatten engine init control flow
> git bisect good bfc882b4e30fbc169ecfe3508378623743806f56
> # good: [2b875c22fa77dfc895d3cf8287a553813d3e64c8] drm/i915: Make intel_plane_state subclass drm_plane_state
> git bisect good 2b875c22fa77dfc895d3cf8287a553813d3e64c8
> # bad: [15a17aae5f803551981a7acc6a4058b247a7452c] drm/i915: Check mask/bit helper functions
> git bisect bad 15a17aae5f803551981a7acc6a4058b247a7452c
> # bad: [146d84f0f2707bfe2c67114eeefac30da8584b3b] drm/i915: Fix up seqno -> request merge issues
> git bisect bad 146d84f0f2707bfe2c67114eeefac30da8584b3b
> # good: [c59cb179aaf444931cf9c547a514e383da3d2526] drm/i915: Consolidate top-level .update_plane() handlers
> git bisect good c59cb179aaf444931cf9c547a514e383da3d2526
> # bad: [cf4c7c12258ed9367f4fc45238f5f50d2db892c1] drm/i915: Make all plane disables use 'update_plane' (v5)
> git bisect bad cf4c7c12258ed9367f4fc45238f5f50d2db892c1
> # good: [e614c3c946ae5b50a679d65d2c981615d8ceccab] drm/i915: Ensure state->crtc is non-NULL for plane updates
> git bisect good e614c3c946ae5b50a679d65d2c981615d8ceccab
> # first bad commit: [cf4c7c12258ed9367f4fc45238f5f50d2db892c1] drm/i915: Make all plane disables use 'update_plane' (v5)
> --
> Michal Hocko
> SUSE Labs
> _______________________________________________
> dri-devel mailing list
> [email protected]
> http://lists.freedesktop.org/mailman/listinfo/dri-devel

--
Jani Nikula, Intel Open Source Technology Center

2015-07-07 08:41:21

by Daniel Vetter

[permalink] [raw]
Subject: Re: WARNING: CPU: 0 PID: 3634 at drivers/gpu/drm/drm_irq.c:1141 drm_wait_one_vblank

On Wed, Jul 01, 2015 at 03:23:39PM +0300, Jani Nikula wrote:
>
> +intel-gfx and Matt
>
> On Wed, 01 Jul 2015, Michal Hocko <[email protected]> wrote:
> > On Wed 01-07-15 10:26:39, Daniel Vetter wrote:
> >> On Tue, Jun 30, 2015 at 10:13:35PM +0200, Michal Hocko wrote:
> >> > On Tue 30-06-15 18:59:29, Daniel Vetter wrote:
> > [...]
> >> > > Also it might be time to start bisecting this if you can readily reproduce it.
> >> >
> >> > Yes, I can reproduce it just by switching to the text console. Sometimes
> >> > it is the first attempt already but sometimes it takes several attempts.
> >> > I will try to go back to 4.0 and bisect it then.
> >>
> >> Yes please do, since this is a confusing regression I think the bisect
> >> result will be the fastest way forward.
> >
> > OK, managed to bisect to cf4c7c12258e ("drm/i915: Make all plane
> > disables use 'update_plane' (v5)") (CC people involved - the thread
> > starts here: http://marc.info/?l=dri-devel&m=143566543432613&w=2 for
> > your reference).
> >
> > I do not see the warning when I revert the commit directly on top of
> > cf4c7c12258e but I cannot cleanly revert it on top of the current Linus'
> > tree. Anything more I can give you to help to further debug the issue?

Ok still haven't grown much clue unfortunately. The bisect just points at
where we started to do that vblank_wait in the codepath that somehow
breaks for you. But we should check whether vblank will work beforehand or
not. It's also strange that it only fails sporadically. Can you please
boot with drm.debug=0xf (lots more nois in dmesg with this) and reproduce?
I only need the last few pages before the WARNING backtrace, just to
understand a bit better what's going on there.

Thanks, Daniel
> >
> > Bisect log is:
> > git bisect start
> > # bad: [c517d838eb7d07bbe9507871fab3931deccff539] Linux 4.0-rc1
> > git bisect bad c517d838eb7d07bbe9507871fab3931deccff539
> > # good: [bfa76d49576599a4b9f9b7a71f23d73d6dcff735] Linux 3.19
> > git bisect good bfa76d49576599a4b9f9b7a71f23d73d6dcff735
> > # good: [02f1f2170d2831b3233e91091c60a66622f29e82] kernel.h: remove ancient __FUNCTION__ hack
> > git bisect good 02f1f2170d2831b3233e91091c60a66622f29e82
> > # bad: [796e1c55717e9a6ff5c81b12289ffa1ffd919b6f] Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux
> > git bisect bad 796e1c55717e9a6ff5c81b12289ffa1ffd919b6f
> > # good: [9682ec9692e5ac11c6caebd079324e727b19e7ce] Merge tag 'driver-core-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
> > git bisect good 9682ec9692e5ac11c6caebd079324e727b19e7ce
> > # good: [a9724125ad014decf008d782e60447c811391326] Merge tag 'tty-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
> > git bisect good a9724125ad014decf008d782e60447c811391326
> > # bad: [f43dff0ee00a259f524ce17ba4f8030553c66590] Merge tag 'drm-amdkfd-next-fixes-2015-01-25' of git://people.freedesktop.org/~gabbayo/linux into drm-next
> > git bisect bad f43dff0ee00a259f524ce17ba4f8030553c66590
> > # good: [b942c653ae265abbd31032f3b4f5f857e5c7c723] Merge tag 'trace-sh-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
> > git bisect good b942c653ae265abbd31032f3b4f5f857e5c7c723
> > # good: [fcf3aac5fc307f0cae429f5844ddc25761662858] drm/i915: remove unused power_well/get_cdclk_freq api
> > git bisect good fcf3aac5fc307f0cae429f5844ddc25761662858
> > # bad: [4f4d89af78682f2ed1cf6745794804817f867bba] Merge tag 'drm-amdkfd-next-2015-01-09' of git://people.freedesktop.org/~gabbayo/linux into drm-next
> > git bisect bad 4f4d89af78682f2ed1cf6745794804817f867bba
> > # bad: [64387b613a43713d0e03d9d43bfbb1727e8475e1] drm/i915: Protect against leaks in pipe_crc_set_source
> > git bisect bad 64387b613a43713d0e03d9d43bfbb1727e8475e1
> > # good: [bfc882b4e30fbc169ecfe3508378623743806f56] drm/i915: Flatten engine init control flow
> > git bisect good bfc882b4e30fbc169ecfe3508378623743806f56
> > # good: [2b875c22fa77dfc895d3cf8287a553813d3e64c8] drm/i915: Make intel_plane_state subclass drm_plane_state
> > git bisect good 2b875c22fa77dfc895d3cf8287a553813d3e64c8
> > # bad: [15a17aae5f803551981a7acc6a4058b247a7452c] drm/i915: Check mask/bit helper functions
> > git bisect bad 15a17aae5f803551981a7acc6a4058b247a7452c
> > # bad: [146d84f0f2707bfe2c67114eeefac30da8584b3b] drm/i915: Fix up seqno -> request merge issues
> > git bisect bad 146d84f0f2707bfe2c67114eeefac30da8584b3b
> > # good: [c59cb179aaf444931cf9c547a514e383da3d2526] drm/i915: Consolidate top-level .update_plane() handlers
> > git bisect good c59cb179aaf444931cf9c547a514e383da3d2526
> > # bad: [cf4c7c12258ed9367f4fc45238f5f50d2db892c1] drm/i915: Make all plane disables use 'update_plane' (v5)
> > git bisect bad cf4c7c12258ed9367f4fc45238f5f50d2db892c1
> > # good: [e614c3c946ae5b50a679d65d2c981615d8ceccab] drm/i915: Ensure state->crtc is non-NULL for plane updates
> > git bisect good e614c3c946ae5b50a679d65d2c981615d8ceccab
> > # first bad commit: [cf4c7c12258ed9367f4fc45238f5f50d2db892c1] drm/i915: Make all plane disables use 'update_plane' (v5)
> > --
> > Michal Hocko
> > SUSE Labs
> > _______________________________________________
> > dri-devel mailing list
> > [email protected]
> > http://lists.freedesktop.org/mailman/listinfo/dri-devel
>
> --
> Jani Nikula, Intel Open Source Technology Center

--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

2015-07-08 06:40:31

by Michal Hocko

[permalink] [raw]
Subject: Re: WARNING: CPU: 0 PID: 3634 at drivers/gpu/drm/drm_irq.c:1141 drm_wait_one_vblank

I have just tried to boot 4.2-rc1 and cannot seem to reproduce the issue
anymore.

On Tue 07-07-15 10:43:58, Daniel Vetter wrote:
[...]
> Can you please
> boot with drm.debug=0xf (lots more nois in dmesg with this) and reproduce?
> I only need the last few pages before the WARNING backtrace, just to
> understand a bit better what's going on there.

And 0xf debug level seem to paper over the problem because I do not see
the warning even with 4.1 where I am able to reproduce this reliably.
This suggests this is a timing sensitive issue.
--
Michal Hocko
SUSE Labs

2015-07-08 07:29:42

by Daniel Vetter

[permalink] [raw]
Subject: Re: WARNING: CPU: 0 PID: 3634 at drivers/gpu/drm/drm_irq.c:1141 drm_wait_one_vblank

On Wed, Jul 08, 2015 at 08:40:17AM +0200, Michal Hocko wrote:
> I have just tried to boot 4.2-rc1 and cannot seem to reproduce the issue
> anymore.
>
> On Tue 07-07-15 10:43:58, Daniel Vetter wrote:
> [...]
> > Can you please
> > boot with drm.debug=0xf (lots more nois in dmesg with this) and reproduce?
> > I only need the last few pages before the WARNING backtrace, just to
> > understand a bit better what's going on there.
>
> And 0xf debug level seem to paper over the problem because I do not see
> the warning even with 4.1 where I am able to reproduce this reliably.
> This suggests this is a timing sensitive issue.

Ok that's starting to get nasty. Can you please test what happens when you
boot with drm.vblankoffdelay=0 and whether drm.vblankoffdelay=1000 has an
effect on reproduction rate? No debug output needed.
-Daniel
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

2015-07-08 07:46:43

by Michal Hocko

[permalink] [raw]
Subject: Re: WARNING: CPU: 0 PID: 3634 at drivers/gpu/drm/drm_irq.c:1141 drm_wait_one_vblank

On Wed 08-07-15 09:32:18, Daniel Vetter wrote:
[...]
> Ok that's starting to get nasty. Can you please test what happens when you
> boot with drm.vblankoffdelay=0 and whether drm.vblankoffdelay=1000 has an
> effect on reproduction rate? No debug output needed.

No difference. See the kernel log from both runs attached.
--
Michal Hocko
SUSE Labs


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