Bug 642010 – >=sys-kernel/gentoo-sources-4.9.34: [drm:intel_set_cpu_fifo_underrun_reporting] *ERROR* uncleared fifo underrun on pipe A

• Product: Gentoo Linux
• Status: RESOLVED NEEDINFO

[Description m.manico 2017-12-22 08:51:12 UTC]

Hi,

since gentoo kernels >4.9.34 I get the following two lines in dmesg (booting 4.14.8):

[drm:intel_set_cpu_fifo_underrun_reporting] *ERROR* uncleared fifo underrun on pipe A
[drm:intel_cpu_fifo_underrun_irq_handler] *ERROR* CPU pipe A FIFO underrun

Scrolling up I found a message about the intel microcode being outdated so I followed
https://wiki.gentoo.org/wiki/Intel_microcode#New_method_without_initram-fs.2Fdisk
but that did not fix it (the microcode loads correctly).

I see similar report when googling but was not able to derive a solution for myself from that research.

fwiw I compared the kernel configs of 4.9.34 (last "working" version) and 4.14.8 (most recent version showing that bug)

uname -a
Linux pax 4.14.8-gentoo-r1 #2 SMP Fri Dec 22 09:21:40 CET 2017 x86_64 Intel(R) Core(TM) i5-4210U CPU @ 1.70GHz GenuineIntel GNU/Linux

diff <(sort kernel-config-4.9.34-gentoo) <(sort linux/.config) | grep -E "[<|>] C"
> CONFIG_ARCH_HAS_ADD_PAGES=y
> CONFIG_ARCH_HAS_FORTIFY_SOURCE=y
< CONFIG_ARCH_HAS_GIGANTIC_PAGE=y
< CONFIG_ARCH_HAS_MMIO_FLUSH=y
> CONFIG_ARCH_HAS_MEM_ENCRYPT=y
> CONFIG_ARCH_HAS_REFCOUNT=y
> CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE=y
> CONFIG_ARCH_HAS_ZONE_DEVICE=y
< CONFIG_ARCH_WANT_FRAME_POINTERS=y
> CONFIG_ARCH_WANTS_THP_SWAP=y
< CONFIG_CIFS_SMB2=y
> CONFIG_DRM_PANEL_BRIDGE=y
< CONFIG_EXTRA_FIRMWARE=""
> CONFIG_EXTRA_FIRMWARE_DIR="/lib/firmware"
> CONFIG_EXTRA_FIRMWARE="intel-ucode/06-45-01"
> CONFIG_FRAME_POINTER_UNWINDER=y
> CONFIG_FUTEX_PI=y
> CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK=y
> CONFIG_GENERIC_IRQ_MIGRATION=y
> CONFIG_HAVE_GENERIC_GUP=y
> CONFIG_HAVE_HARDLOCKUP_DETECTOR_PERF=y
> CONFIG_HAVE_MOD_ARCH_SPECIFIC=y
> CONFIG_HAVE_RCU_TABLE_FREE=y
> CONFIG_HID_ITE=y
> CONFIG_IR_JVC_DECODER=y
> CONFIG_IR_MCE_KBD_DECODER=y
> CONFIG_IR_NEC_DECODER=y
> CONFIG_IR_RC5_DECODER=y
> CONFIG_IR_RC6_DECODER=y
> CONFIG_IR_SANYO_DECODER=y
> CONFIG_IR_SHARP_DECODER=y
> CONFIG_IR_SONY_DECODER=y
> CONFIG_IR_XMP_DECODER=y
> CONFIG_MDIO_BUS=y
< CONFIG_MMC_BLOCK_BOUNCE=y
> CONFIG_NET_VENDOR_HUAWEI=y
> CONFIG_NVMEM=y
> CONFIG_PCI_LOCKLESS_CONFIG=y
> CONFIG_RC_CORE=y
> CONFIG_RC_DECODERS=y
> CONFIG_RC_MAP=y
> CONFIG_RTC_NVMEM=y
> CONFIG_SLAB_MERGE_DEFAULT=y
> CONFIG_SND_SEQ_DEVICE=y
> CONFIG_SND_SEQ_MIDI_EVENT=y
> CONFIG_THIN_ARCHIVES=y
> CONFIG_VIDEO_IR_I2C=y
> CONFIG_WATCHDOG_HANDLE_BOOT_ENABLED=y
> CONFIG_WLAN_VENDOR_QUANTENNA=y

Kind regards

[Comment 1 m.manico 2017-12-22 09:22:49 UTC]

Following
https://bbs.archlinux.org/viewtopic.php?id=196370
https://bbs.archlinux.org/viewtopic.php?id=198157

which recommend to edit

/etc/X11/xorg.conf.d/20-intel.conf :
Section "Device"
Identifier "Intel Graphics"
Driver "intel"
Option "AccelMethod" "uxa"
#Option "AccelMethod" "sna"
EndSection

Resulted in X11 not starting and the FIFO underrun messages remaining in dmesg.

Following
https://01.org/linuxgraphics/forum/graphics-update-tool-discussions/drmintelcpufifounderrunirqhandler-i915-error-cpu-pipe-fifo

which recommends to append `i915.enable_rc6=0` to the kernel command line prevents X11 from starting but at least there are no more FIFO underrun messages in dmesg.

[Comment 2 Andreas Sturmlechner 2017-12-22 10:39:29 UTC]

Good old fifo underrun. My laptop had them for years before it died. Upstream is the place to get in touch with, there are existing bugs for this on https://bugs.freedesktop.org/

[Comment 3 Stefano 2018-01-07 14:40:34 UTC]

I can confirm the same behavior, plus screen going to black, on 4.14.11-r2. Le sigh. This bug seemingly just won't die.

[Comment 4 Alice Ferrazzi 2018-01-14 13:55:35 UTC]

still problem with 4.14.13 ?

[Comment 5 m.manico 2018-06-25 23:03:38 UTC]

I am on 4.9.95
The messages are gone.