Bug 95461

Created attachment 172091 [details]
lspci -vvnn

Confirming the above when using linux-4.0-rc5

Extracted from the dmesg file:

[drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe A FIFO underrun

Defining the hardware (relevant lines from the output of an lspci -nnv command):

00:02.0 VGA compatible controller [0300]: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller [8086:2a42] (rev 07) (prog-if 00 [VGA controller])
	Subsystem: Dell Device [1028:0263]
	Flags: bus master, fast devsel, latency 0, IRQ 28
	Memory at f6c00000 (64-bit, non-prefetchable) [size=4M]
	Memory at e0000000 (64-bit, prefetchable) [size=256M]
	I/O ports at efe8 [size=8]
	Expansion ROM at <unassigned> [disabled]
	Capabilities: [90] MSI: Enable+ Count=1/1 Maskable- 64bit-
	Capabilities: [d0] Power Management version 3
	Kernel driver in use: i915

Hi Alan,

You ouput of dmesg please.

Thanks,
--
Cristian

Created attachment 172451 [details]
Complete dmesg file.

The complete dmesg file, as requested.

Oummm, thanks Alan.

One problem, I'see not message of bug similar(?) to:

"[    1.734792] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe A FIFO underrun
[    1.735468] [drm:cpt_set_fifo_underrun_reporting [i915]] *ERROR* uncleared pch fifo underrun on pch transcoder A
[    1.735500] [drm:intel_pch_fifo_underrun_irq_handler [i915]] *ERROR* PCH transcoder A FIFO underrun"

Please set drm.debug=14 module parameter and attach dmesg all the way from boot
to the problem. Thanks.

Many thanks for you time.
--
Cristian

Hello Jani Nikula,

I'm adding for you information. Duplicated of https://bugzilla.kernel.org/show_bug.cgi?id=85951? I'm completed secure.

Thanks for you work,
--
Cristian

* I'm not completed secure.

I'm fairly confident the bug as reported in comment #0 is fixed in current Linus' master (not tagged as v4.0-rc6 yet, but it's there in the tree). Please reopen if the problem persists with that.

Hmm, well, at least the WARNING backtraces should be gone. Not so confident about the underruns. :(

(In reply to Jani Nikula from comment #8)
> I'm fairly confident the bug as reported in comment #0 is fixed in current
> Linus' master (not tagged as v4.0-rc6 yet, but it's there in the tree).
> Please reopen if the problem persists with that.

I will wait for linux-4.0-rc6 and then re-check.

Hello Alan,

Testing kernel ThE sunday.  Information The monday :)

Many thank for you work,
..
Cristian

Created attachment 172671 [details]
dmesg_4.0.0-040000rc6-generic.txt

dmesg output in kernel 4.0-rc6 D: idem problem....

[    1.748191] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe A FIFO underrun
[    1.748324] usb 4-1: New USB device found, idVendor=8087, idProduct=0024
[    1.748327] usb 4-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
[    1.748729] hub 4-1:1.0: USB hub found
[    1.748986] hub 4-1:1.0: 6 ports detected
[    1.750471] [drm:cpt_set_fifo_underrun_reporting [i915]] *ERROR* uncleared pch fifo underrun on pch transcoder A
[    1.750515] [drm:intel_pch_fifo_underrun_irq_handler [i915]] *ERROR* PCH transcoder A FIFO underrun

Tested with linux-4.0-rc6 (on a RHEL6 system).

Still seeing the following error message in the dmesg file --

[drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe A FIFO underrun

Created attachment 172721 [details]
Complete dmesg file.

Hello fengguang.wu developer,

We detail here, you could support us?

Thanks for you work,
--
Cristian

A kernel using the linux-4.0-rc7 sources was built --

Linux Duo2 4.0.0-0.rc7.el6.elrepo.x86_64 #1 SMP Mon Apr 6 21:27:18 EDT 2015 x86_64 x86_64 x86_64 GNU/Linux

Upon boot the error CPU pipe A FIFO underrun message is still seen --

[drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe A FIFO underrun

The complete dmesg file is attached.

This bug is NOT resolved with a code fix.

Created attachment 173561 [details]
Complete dmesg file.

(In reply to Alan Bartlett from comment #16)
> This bug is NOT resolved with a code fix.

REOPEN.

Created attachment 174321 [details]
dmesg_4.0.0-040000-generic.txt

[    1.746621] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe A FIFO underrun
[    1.746713] ata2.00: ATA-9: SanDisk SSD i100 24GB, 11.50.04, max UDMA/133
[    1.746717] ata2.00: 46905264 sectors, multi 1: LBA48 NCQ (depth 31/32)
[    1.746784] hub 4-1:1.0: USB hub found
[    1.746857] hub 4-1:1.0: 6 ports detected
[    1.747037] ata1.00: ATA-8: Hitachi HTS545050A7E380, GG2OA6C0, max UDMA/133
[    1.747040] ata1.00: 976773168 sectors, multi 16: LBA48 NCQ (depth 31/32), AA
[    1.747093] [drm:cpt_set_fifo_underrun_reporting [i915]] *ERROR* uncleared pch fifo underrun on pch transcoder A
[    1.747125] [drm:intel_pch_fifo_underrun_irq_handler [i915]] *ERROR* PCH transcoder A FIFO underrun

Created attachment 177611 [details]
dmesg_4.1.0-040000rc4-generic.txt

Thanks for you work.
--
Cristian

^^ -> [    1.720741] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe A FIFO underrun
[    1.721505] [drm:cpt_set_fifo_underrun_reporting [i915]] *ERROR* uncleared pch fifo underrun on pch transcoder A
[    1.721539] [drm:intel_pch_fifo_underrun_irq_handler [i915]] *ERROR* PCH transcoder A FIFO underrun

Please add drm.debug=0x1e to your kernel command line and upload dmesg again.

A kernel was built from the linux-4.1-rc5 sources.

A normal boot results in seeing --

[quote]
[drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe A FIFO underrun
[/quote]

The attached dmesg-1.txt file originates from that boot.

Rebooted with drm.debug=0x1e appended to the kernel command line. The above error message was not then seen.

The attached dmesg-2.txt file originates from that boot.

Created attachment 177971 [details]
Dmesg file, normal boot.

Created attachment 177981 [details]
Dmesg file, booted with drm.debug=0x1e appended to kernel command line.

Kernel --

4.1-rc8

Error message still present --

[drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe A FIFO underrun

Created attachment 180411 [details]
Full dmesg file for kernel 4.1-rc8

Created attachment 180451 [details]
Full dmesg file, kernel booted with drm.debug=0x1e

I am able to reproduce this with Lenovo T60.

```
$ sudo lspci -v -s 0:02
00:02.0 VGA compatible controller: Intel Corporation Mobile 945GM/GMS, 943/940GML Express Integrated Graphics Controller (rev 03) (prog-if 00 [VGA controller])
	Subsystem: Lenovo ThinkPad R60/T60/X60 series
	Flags: bus master, fast devsel, latency 0, IRQ 16
	Memory at e4300000 (32-bit, non-prefetchable) [size=512K]
	I/O ports at 50a0 [size=8]
	Memory at d0000000 (32-bit, prefetchable) [size=256M]
	Memory at e4400000 (32-bit, non-prefetchable) [size=256K]
	Expansion ROM at <unassigned> [disabled]
	Capabilities: [90] MSI: Enable- Count=1/1 Maskable- 64bit-
	Capabilities: [d0] Power Management version 2
	Kernel driver in use: i915

00:02.1 Display controller: Intel Corporation Mobile 945GM/GMS/GME, 943/940GML Express Integrated Graphics Controller (rev 03)
	Subsystem: Lenovo ThinkPad R60/T60/X60 series
	Flags: bus master, fast devsel, latency 0
	Memory at e4380000 (32-bit, non-prefetchable) [size=512K]
	Capabilities: [d0] Power Management version 2

```

```
Sep 26 19:12:12 my-t60 kernel: [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe A FIFO underrun
Sep 26 19:12:12 my-t60 kernel: [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe B FIFO underrun
```

Linux 4.2 is used.

I am unable to reproduce this with a Lenovo X60 (Intel IGD) laptop.

*** This bug has been marked as a duplicate of bug 79261 ***

I've reproduced this error with kernel 4.5

sudo lspci -v -s 0:02
00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09) (prog-if 00 [VGA controller])
	Subsystem: Dell 2nd Generation Core Processor Family Integrated Graphics Controller
	Flags: bus master, fast devsel, latency 0, IRQ 31
	Memory at c0000000 (64-bit, non-prefetchable) [size=4M]
	Memory at b0000000 (64-bit, prefetchable) [size=256M]
	I/O ports at 4000 [size=64]
	Expansion ROM at <unassigned> [disabled]
	Capabilities: [90] MSI: Enable+ Count=1/1 Maskable- 64bit-
	Capabilities: [d0] Power Management version 2
	Capabilities: [a4] PCI Advanced Features
	Kernel driver in use: i915
	Kernel modules: i915

last part of dmesg:

[ +32,012300] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe A FIFO underrun
[  +0,001882] [drm:intel_set_pch_fifo_underrun_reporting [i915]] *ERROR* uncleared pch fifo underrun on pch transcoder A
[  +0,000025] [drm:intel_pch_fifo_underrun_irq_handler [i915]] *ERROR* PCH transcoder A FIFO underrun
[  +0,029961] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe B FIFO underrun
[  +0,056379] [drm:intel_set_pch_fifo_underrun_reporting [i915]] *ERROR* uncleared pch fifo underrun on pch transcoder B
[  +0,031279] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe B FIFO underrun
[  +0,032886] [drm:intel_check_pch_fifo_underruns [i915]] *ERROR* pch fifo underrun on pch transcoder B

uname -a
Linux mymachine-XPS-L412Z 4.5.0-040500rc6-generic #201602281230 SMP Sun Feb 28 17:33:02 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux

Created attachment 219381 [details]
full dmesg for my machine

Dmesg from my machine full

(In reply to Cruz Fernandez from comment #33)
> I've reproduced this error with kernel 4.5

All drm/i915 bug tracking happens at http://bugs.freedesktop.org/ now.