Running this also works (disabling intel_idle.max_cstate=1 on grub). #!/bin/sh
#title: c6off+c7on.sh #description: Disables all C6 and enables all C7 core states for Baytrail CPUs #author: Wolfgang Reimer <linuxball (at) gmail.com> #date: 20190616 #version: 2.0 #usage: sudo <path>/c6off+c7on.sh #notes: Intended as test script to verify whether erratum VLP52 (see # [1]) is the root cause for kernel bug 109051 (see [2]). In order # for this to work you must _NOT_ use boot parameter # intel_idle.max_cstate=<number>. # # [1] http://www.intel.com/content/dam/www/public/us/en/documents/specification-updates/pentium-n3520-j2850-celeron-n2920-n2820-n2815-n2806-j1850-j1750-spec-update.pdf # [2] https://bugzilla.kernel.org/show_bug.cgi?id=109051 # Disable ($1 == 1) or enable ($1 == 0) core state, if not yet done. disable() { local action read disabled <disable test "$disabled" = $1 && return echo $1 >disable || return action=ENABLED; test "$1" = 0 || action=DISABLED printf "%-8s state %7s for %s.\n" $action "$name" $cpu } # Iterate through each core state and for Baytrail (BYT) disable all C6 # and enable all C7 states. cd /sys/devices/system/cpu for cpu in cpu[0-9]*; do for dir in $cpu/cpuidle/state*; do cd "$dir" read name <name case $name in C6*) disable 1;; C7*) disable 0;; esac cd ../../.. done done ** Bug watch added: Linux Kernel Bug Tracker #109051 https://bugzilla.kernel.org/show_bug.cgi?id=109051 -- 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/1833169 Title: intel_max_cstate is needed with baytrail to aviod hangups Status in linux package in Ubuntu: Incomplete Bug description: https://bugzilla.kernel.org/show_bug.cgi?id=109051 fix (will be merged on 5.2 merge window, so I will need backport): https://cgit.freedesktop.org/drm-intel/commit/?id=a75d035fedbdecf83f86767aa2e4d05c8c4ffd95 ProblemType: Bug DistroRelease: Ubuntu 18.04 Package: linux-generic-hwe-18.04 4.18.0.21.71 ProcVersionSignature: Ubuntu 4.18.0-21.22~18.04.1-generic 4.18.20 Uname: Linux 4.18.0-21-generic x86_64 ApportVersion: 2.20.9-0ubuntu7.6 Architecture: amd64 CurrentDesktop: ubuntu:GNOME Date: Tue Jun 18 08:14:08 2019 EcryptfsInUse: Yes InstallationDate: Installed on 2019-06-17 (0 days ago) InstallationMedia: Ubuntu 18.04.2 LTS "Bionic Beaver" - Release amd64 (20190210) SourcePackage: linux-meta-hwe UpgradeStatus: No upgrade log present (probably fresh install) --- ProblemType: Bug ApportVersion: 2.20.9-0ubuntu7.6 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC1: jaime 1741 F.... pulseaudio /dev/snd/controlC0: jaime 1741 F.... pulseaudio CurrentDesktop: ubuntu:GNOME DistroRelease: Ubuntu 18.04 EcryptfsInUse: Yes InstallationDate: Installed on 2019-06-17 (3 days ago) InstallationMedia: Ubuntu 18.04.2 LTS "Bionic Beaver" - Release amd64 (20190210) Lsusb: Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 001 Device 003: ID 8087:07dc Intel Corp. Bus 001 Device 002: ID 04f2:b490 Chicony Electronics Co., Ltd Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub MachineType: GOOGLE Gnawty Package: linux (not installed) ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.18.0-22-generic root=UUID=b12b3d55-99d9-45f0-87f5-46cedaeb5806 ro quiet splash intel_idle.max_cstate=1 vt.handoff=1 ProcVersionSignature: Ubuntu 4.18.0-22.23~18.04.1-generic 4.18.20 RelatedPackageVersions: linux-restricted-modules-4.18.0-22-generic N/A linux-backports-modules-4.18.0-22-generic N/A linux-firmware 1.173.6 Tags: wayland-session bionic Uname: Linux 4.18.0-22-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo _MarkForUpload: True dmi.bios.date: 08/18/2014 dmi.bios.vendor: coreboot dmi.chassis.type: 3 dmi.chassis.vendor: GOOGLE dmi.modalias: dmi:bvncoreboot:bvr:bd08/18/2014:svnGOOGLE:pnGnawty:pvr1.0:cvnGOOGLE:ct3:cvr: dmi.product.name: Gnawty dmi.product.version: 1.0 dmi.sys.vendor: GOOGLE To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1833169/+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
