Yes, it isn’t ideal and sort of defeats the ‘low latency’ object, but it’s better than having your SSD thwacked (one of these writes to the log per second also adds up in terms of CPU activity).
As the patch is just a one-liner, which allows execution in both soft and hard interrupt contexts instead of hard only, and has been tested and pushed upstream (http://comments.gmane.org/gmane.comp.video.dri.devel/122993) I’d hope the kernel devs will be able to merge this in in time for Vivid. -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to xserver-xorg-video-intel in Ubuntu. https://bugs.launchpad.net/bugs/1430230 Title: Log flooding with warning message when using linux-lowlatency kernel Status in One Hundred Papercuts: Confirmed Status in X.org xf86-video-intel: Fix Released Status in linux-meta-lowlatency package in Ubuntu: New Status in xserver-xorg-video-intel package in Ubuntu: Confirmed Bug description: In Vivid, when booting with lowlatency kernel (and possibly with generic kernel and threadirqs), Intel graphics driver will flood the logs with warning: Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247652] ------------[ cut here ]------------ Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247683] WARNING: CPU: 3 PID: 659 at /build/buildd/linux-3.19.0/drivers/gpu/drm/i915/intel_display.c:9705 intel_check_page_flip+0xa2/0xf0 [i915]() Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247685] WARN_ON(!in_irq()) Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247686] Modules linked in: md4 nls_utf8 cifs fscache msr acpi_call(OE) xt_CHECKSUM iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 bridge stp llc ebtable_filter ebtables pci_stub vboxpci(OE) vboxnetadp(OE) vboxnetflt(OE) vboxdrv(OE) binfmt_misc rfcomm bnep nls_iso8859_1 hid_apple intel_rapl iosf_mbi x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel uvcvideo kvm videobuf2_vmalloc videobuf2_memops crct10dif_pclmul i915 videobuf2_core crc32_pclmul ghash_clmulni_intel v4l2_common videodev aesni_intel media aes_x86_64 btusb lrw gf128mul glue_helper bluetooth ablk_helper cryptd arc4 snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic iwldvm dm_multipath scsi_dh snd_hda_intel mac80211 snd_hda_controller snd_hda_codec joydev snd_hwdep serio_raw drm_kms_helper iwlwifi snd_pcm thinkpad_acpi cfg80211 snd_seq_midi snd_seq_midi_event nvram snd_rawmidi snd_seq ip6t_REJECT nf_reject_ipv6 snd_seq_device nf_log_ipv6 lpc_ich snd_timer drm shpchp xt_hl snd mei_me nf_conntrack_ipv6 mei nf_defrag_ipv6 i2c_algo_bit ip6t_rt soundcore wmi video mac_hid ipt_REJECT nf_reject_ipv4 nf_log_ipv4 nf_log_common xt_LOG xt_multiport xt_limit xt_tcpudp nf_conntrack_ipv4 nf_defrag_ipv4 xt_addrtype xt_conntrack ip6table_filter ip6_tables nf_conntrack_netbios_ns nf_conntrack_broadcast cuse nf_nat_ftp nf_nat nf_conntrack_ftp parport_pc nf_conntrack ppdev iptable_filter ip_tables lp x_tables parport autofs4 btrfs xor raid6_pq hid_generic usbhid hid psmouse ahci e1000e sdhci_pci libahci sdhci ptp pps_core Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247768] CPU: 3 PID: 659 Comm: irq/32-i915 Tainted: G W OE 3.19.0-7-lowlatency #7-Ubuntu Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247770] Hardware name: LENOVO 2353CTO/2353CTO, BIOS G7ETA0WW (2.60 ) 05/14/2014 Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247781] ffffffffc0be7010 ffff88042a353c98 ffffffff817c5402 ffff88043e2cfd78 Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247784] ffff88042a353ce8 ffff88042a353cd8 ffffffff8107738a ffff88042a353cd8 Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247786] ffff880428f3f000 ffff880428f5e800 0000000000000000 0000000000000000 Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247788] Call Trace: Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247795] [<ffffffff817c5402>] dump_stack+0x4c/0x6e Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247805] [<ffffffff8107738a>] warn_slowpath_common+0x8a/0xc0 Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247814] [<ffffffff81077406>] warn_slowpath_fmt+0x46/0x50 Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247830] [<ffffffffc0b92482>] intel_check_page_flip+0xa2/0xf0 [i915] Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247843] [<ffffffffc0b5f4d8>] ironlake_irq_handler+0x428/0x1010 [i915] Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247847] [<ffffffff8109b55d>] ? finish_task_switch+0x5d/0x100 Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247854] [<ffffffff810cfc60>] ? irq_thread_fn+0x50/0x50 Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247858] [<ffffffff810cfc8d>] irq_forced_thread_fn+0x2d/0x70 Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247861] [<ffffffff810d01af>] irq_thread+0x11f/0x150 Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247865] [<ffffffff810cfd00>] ? wake_threads_waitq+0x30/0x30 Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247868] [<ffffffff810d0090>] ? irq_thread_check_affinity+0x90/0x90 Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247871] [<ffffffff81095bc9>] kthread+0xc9/0xe0 Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247874] [<ffffffff81095b00>] ? kthread_create_on_node+0x1c0/0x1c0 Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247877] [<ffffffff817cc33c>] ret_from_fork+0x7c/0xb0 Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247880] [<ffffffff81095b00>] ? kthread_create_on_node+0x1c0/0x1c0 Mar 10 09:35:43 franck-ThinkPad-T430s kernel: [ 2216.247883] ---[ end trace fa4376848cde145f ]--- There seems to be a bug report here https://bugs.freedesktop.org/show_bug.cgi?id=89321 ProblemType: Bug DistroRelease: Ubuntu 15.04 Package: xserver-xorg-video-intel 2:2.99.917-1~exp1ubuntu2 ProcVersionSignature: Ubuntu 3.19.0-7.7-generic 3.19.0 Uname: Linux 3.19.0-7-generic x86_64 .tmp.unity.support.test.0: ApportVersion: 2.16.2-0ubuntu2 Architecture: amd64 CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins' CompositorRunning: compiz CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0' CompositorUnredirectFSW: true CurrentDesktop: Unity Date: Tue Mar 10 10:46:28 2015 DistUpgraded: 2015-03-09 18:17:36,430 DEBUG enabling apt cron job DistroCodename: vivid DistroVariant: ubuntu DkmsStatus: acpi-call, 1.1.0, 3.19.0-7-generic, x86_64: installed virtualbox, 4.3.24, 3.19.0-7-generic, x86_64: installed ExtraDebuggingInterest: Yes GraphicsCard: Intel Corporation 3rd Gen Core processor Graphics Controller [8086:0166] (rev 09) (prog-if 00 [VGA controller]) Subsystem: Lenovo Device [17aa:21fb] InstallationDate: Installed on 2014-12-13 (86 days ago) InstallationMedia: Ubuntu 14.10 "Utopic Unicorn" - Release amd64 (20141022.1) MachineType: LENOVO 2353CTO ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-3.19.0-7-generic.efi.signed root=/dev/mapper/ubuntu--vg-lv--root ro quiet splash nomdmonddf nomdmonisw vt.handoff=7 SourcePackage: xserver-xorg-video-intel UpgradeStatus: Upgraded to vivid on 2015-03-09 (0 days ago) dmi.bios.date: 05/14/2014 dmi.bios.vendor: LENOVO dmi.bios.version: G7ETA0WW (2.60 ) dmi.board.asset.tag: Not Available dmi.board.name: 2353CTO dmi.board.vendor: LENOVO dmi.board.version: Not Defined dmi.chassis.asset.tag: No Asset Information dmi.chassis.type: 10 dmi.chassis.vendor: LENOVO dmi.chassis.version: Not Available dmi.modalias: dmi:bvnLENOVO:bvrG7ETA0WW(2.60):bd05/14/2014:svnLENOVO:pn2353CTO:pvrThinkPadT430s:rvnLENOVO:rn2353CTO:rvrNotDefined:cvnLENOVO:ct10:cvrNotAvailable: dmi.product.name: 2353CTO dmi.product.version: ThinkPad T430s dmi.sys.vendor: LENOVO version.compiz: compiz 1:0.9.12.1+15.04.20150303-0ubuntu1 version.ia32-libs: ia32-libs N/A version.libdrm2: libdrm2 2.4.59-0ubuntu1 version.libgl1-mesa-dri: libgl1-mesa-dri 10.5.0-0ubuntu1 version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A version.libgl1-mesa-glx: libgl1-mesa-glx 10.5.0-0ubuntu1 version.xserver-xorg-core: xserver-xorg-core 2:1.16.2.901-1ubuntu4 version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.9.0-1ubuntu2 version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.4.0-2ubuntu2 version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917-1~exp1ubuntu2 version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.11-1ubuntu2 xserver.bootTime: Tue Mar 10 10:09:26 2015 xserver.configfile: default xserver.errors: xserver.logfile: /var/log/Xorg.0.log xserver.outputs: product id 12876 vendor SEC xserver.version: 2:1.16.2.901-1ubuntu4 To manage notifications about this bug go to: https://bugs.launchpad.net/hundredpapercuts/+bug/1430230/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp

