Olivier Diotte, thank you for taking the time to report this bug and helping to make Ubuntu better. Please execute the following command only once, as it will automatically gather debugging information, in a terminal: apport-collect 1474538
** Package changed: linux-lts-vivid (Ubuntu) => linux (Ubuntu) ** Changed in: linux (Ubuntu) Importance: Undecided => Low ** Changed in: linux (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1474538 Title: nouveau driver fills syslog when running xscreensaver (molecule) Status in Nouveau Xorg driver: Confirmed Status in linux package in Ubuntu: Incomplete Bug description: nouveau fills /var/log/kern.log and /var/log/syslog with _very_ frequent messages when the molecule xscreensaver is running. This is a big problem as it prevents me from letting my machine do anything overnight (with the screenlock on). I haven't tested other screensavers and don't appear to get messages otherwise. Here is an excerpt: ====================8< CUT HERE 8<================================================================= $ tail -n 3000 kern.log.1 | head -n 50 Jul 10 18:02:35 dioo-XPS kernel: [114893.357149] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:35 dioo-XPS kernel: [114893.406261] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:35 dioo-XPS kernel: [114893.406269] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:35 dioo-XPS kernel: [114893.420442] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:35 dioo-XPS kernel: [114893.420447] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:35 dioo-XPS kernel: [114893.479210] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:35 dioo-XPS kernel: [114893.479217] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:35 dioo-XPS kernel: [114893.568349] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:35 dioo-XPS kernel: [114893.568356] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:35 dioo-XPS kernel: [114893.622806] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:35 dioo-XPS kernel: [114893.622813] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:35 dioo-XPS kernel: [114893.637217] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:35 dioo-XPS kernel: [114893.637221] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:35 dioo-XPS kernel: [114893.695836] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:35 dioo-XPS kernel: [114893.695843] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:35 dioo-XPS kernel: [114893.784309] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:35 dioo-XPS kernel: [114893.784316] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:35 dioo-XPS kernel: [114893.838180] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:35 dioo-XPS kernel: [114893.838187] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:35 dioo-XPS kernel: [114893.853754] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:35 dioo-XPS kernel: [114893.853759] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:35 dioo-XPS kernel: [114893.913521] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:35 dioo-XPS kernel: [114893.913528] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:35 dioo-XPS kernel: [114893.977242] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:35 dioo-XPS kernel: [114893.977249] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:35 dioo-XPS kernel: [114894.068780] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:35 dioo-XPS kernel: [114894.068788] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:35 dioo-XPS kernel: [114894.122599] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:35 dioo-XPS kernel: [114894.122606] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:35 dioo-XPS kernel: [114894.137025] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:35 dioo-XPS kernel: [114894.137030] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:35 dioo-XPS kernel: [114894.195675] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:35 dioo-XPS kernel: [114894.195682] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:36 dioo-XPS kernel: [114894.284069] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:36 dioo-XPS kernel: [114894.284078] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:36 dioo-XPS kernel: [114894.339830] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:36 dioo-XPS kernel: [114894.339837] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:36 dioo-XPS kernel: [114894.353411] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:36 dioo-XPS kernel: [114894.353416] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:36 dioo-XPS kernel: [114894.412188] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:36 dioo-XPS kernel: [114894.412204] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:36 dioo-XPS kernel: [114894.501906] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:36 dioo-XPS kernel: [114894.501913] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:36 dioo-XPS kernel: [114894.558826] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:36 dioo-XPS kernel: [114894.558831] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:36 dioo-XPS kernel: [114894.570001] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:36 dioo-XPS kernel: [114894.570006] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:36 dioo-XPS kernel: [114894.628831] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ Jul 10 18:02:36 dioo-XPS kernel: [114894.628839] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: ch 2 [Xorg[16558]] subc 5 mthd 0x0000 data 0x0000906e Jul 10 18:02:36 dioo-XPS kernel: [114894.717193] nouveau E[ PFIFO][0000:01:00.0] PBDMA0: LBREQ ====================8< CUT HERE 8<================================================================== Both log files are actually 99GiB (they'd be bigger, but at that point my / partition was full). Both files contain almost 975M lines each (which is quite a lot for a file that gets rotated daily!) I run a minimal system (log in to the console, start i3 with startx) and I have a keybinding to launch a xscreensaver (specifically the molecule screensaver from xscreensaver-gl-extra). I had no problem under Ubuntu 15.04 32 bits, but for work-related reasons, I had to downgrade to 14.04 (64 bits). Both the default kernel (I don't remember which version it was) and 3.19.0-22 exhibit the problem. $ lspci -nn | grep VGA 01:00.0 VGA compatible controller [0300]: NVIDIA Corporation Device [10de:1286] (rev a1) I am not sure if this is relevant, but I have three screens all connected to the nVidia card. ProblemType: Bug DistroRelease: Ubuntu 14.04 Package: linux-image-3.19.0-22-generic 3.19.0-22.22~14.04.1 ProcVersionSignature: Ubuntu 3.19.0-22.22~14.04.1-generic 3.19.8-ckt1 Uname: Linux 3.19.0-22-generic x86_64 ApportVersion: 2.14.1-0ubuntu3.11 Architecture: amd64 Date: Tue Jul 14 15:31:42 2015 InstallationDate: Installed on 2015-07-03 (10 days ago) InstallationMedia: Ubuntu 14.04.2 LTS "Trusty Tahr" - Release amd64 (20150218.1) SourcePackage: linux-lts-vivid UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/nouveau/+bug/1474538/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp