[Kernel-packages] [Bug 1763817] Re: [SRU][BIONIC] after enabling cppc dmesg fills with "ACPI CPPC: PCC check channel failed. Status=0"
>From playing around it appears about 300 seconds after boot. I was able to recreate this with kernel 4.15.0-29-generic but no longer after running apt upgrade and rebooting to the 4.15.0-36-generic kernel. -- 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/1763817 Title: [SRU][BIONIC] after enabling cppc dmesg fills with "ACPI CPPC: PCC check channel failed. Status=0" Status in linux package in Ubuntu: Incomplete Bug description: [Impact] On ARM64 systems enabling cppccontrol=1 in firmware, the dmesg fills with messages like: [ 4083.960332] ACPI CPPC: PCC check channel failed. Status=0 [ 4085.546975] ACPI CPPC: PCC check channel failed. Status=0 [ 4113.939921] ACPI CPPC: PCC check channel failed. Status=0 [ 4115.531777] ACPI CPPC: PCC check channel failed. Status=0 We lose any useful data in dmesg and on the console. [Fix] upstream commit fixes this issue: commit 3d41386d556db9f720e00de3e11e45f39cb5071c Author: George Cherian Date: Fri Mar 23 03:30:31 2018 -0700 cpufreq: CPPC: Use transition_delay_us depending transition_latency [Testing] -- before kernel patch -- Both console output and dmesg are filled with the message ACPI CPPC: PCC check channel failed. Status=0 [ 85.969952] ACPI CPPC: PCC check channel failed. Status=0 [ 81.888445] cloud-init[4810]: Cloud-init v. 18.2 running 'modules:final' at Fri, 13 Apr 2018 19:11:57 +. Up 80.71 seconds. [ 81.888625] cloud-init[4810]: Cloud-init v. 18.2 finished at Fri, 13 Apr 2018 19:11:58 +. Datasource DataSourceMAAS [http://10.228.68.5:5240/MAAS/metadata/]. Up 81.69 seconds [ OK ] Started Execute cloud user/final scripts. [ OK ] Reached target Cloud-init target. [ 86.230432] ACPI CPPC: PCC check channel failed. Status=0 [ 86.701943] ACPI CPPC: PCC check channel failed. Status=0 [ 86.773668] ACPI CPPC: PCC check channel failed. Status=0 [ 87.369958] ACPI CPPC: PCC check channel failed. Status=0 [ 87.733361] ACPI CPPC: PCC check channel failed. Status=0 [ 88.207372] ACPI CPPC: PCC check channel failed. Status=0 ubuntu@starbuck:~$ uname -a Linux starbuck 4.15.0-13-generic #14-Ubuntu SMP Sat Mar 17 13:44:36 UTC 2018 aarch64 aarch64 aarch64 GNU/Linux -- after kernel patch -- OK ] Started Apply the settings specified in cloud-config. Starting Execute cloud user/final scripts... [ 67.178425] cloud-init[3688]: Cloud-init v. 18.2 running 'modules:final' at Fri, 13 Apr 2018 20:41:15 +. Up 65.98 seconds. [ 67.200190] cloud-init[3688]: Cloud-init v. 18.2 finished at Fri, 13 Apr 2018 20:41:15 +. Datasource DataSourceMAAS [http://10.228.68.5:5240/MAAS/metadata/]. Up 66.83 seconds [ OK ] Started Execute cloud user/final scripts. [ OK ] Reached target Cloud-init target. Ubuntu Bionic Beaver (development branch) starbuck ttyAMA0 starbuck login: ubuntu@starbuck:~$ uname -a Linux starbuck 4.15.0-15-generic #16~lp1763817+build.1 SMP Fri Apr 13 19:54:10 UTC 2018 aarch64 aarch64 aarch64 GNU/Linux [Regression Potential] None. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1763817/+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
[Kernel-packages] [Bug 1763817] Re: [SRU][BIONIC] after enabling cppc dmesg fills with "ACPI CPPC: PCC check channel failed. Status=0"
I did a clean install of BIONIC via ubuntu-18.04.1-server-arm64.iso on an ARM system and encountered this on first boot. I am happy to send logs but apport-collect states that I am not the owner -- 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/1763817 Title: [SRU][BIONIC] after enabling cppc dmesg fills with "ACPI CPPC: PCC check channel failed. Status=0" Status in linux package in Ubuntu: Incomplete Bug description: [Impact] On ARM64 systems enabling cppccontrol=1 in firmware, the dmesg fills with messages like: [ 4083.960332] ACPI CPPC: PCC check channel failed. Status=0 [ 4085.546975] ACPI CPPC: PCC check channel failed. Status=0 [ 4113.939921] ACPI CPPC: PCC check channel failed. Status=0 [ 4115.531777] ACPI CPPC: PCC check channel failed. Status=0 We lose any useful data in dmesg and on the console. [Fix] upstream commit fixes this issue: commit 3d41386d556db9f720e00de3e11e45f39cb5071c Author: George Cherian Date: Fri Mar 23 03:30:31 2018 -0700 cpufreq: CPPC: Use transition_delay_us depending transition_latency [Testing] -- before kernel patch -- Both console output and dmesg are filled with the message ACPI CPPC: PCC check channel failed. Status=0 [ 85.969952] ACPI CPPC: PCC check channel failed. Status=0 [ 81.888445] cloud-init[4810]: Cloud-init v. 18.2 running 'modules:final' at Fri, 13 Apr 2018 19:11:57 +. Up 80.71 seconds. [ 81.888625] cloud-init[4810]: Cloud-init v. 18.2 finished at Fri, 13 Apr 2018 19:11:58 +. Datasource DataSourceMAAS [http://10.228.68.5:5240/MAAS/metadata/]. Up 81.69 seconds [ OK ] Started Execute cloud user/final scripts. [ OK ] Reached target Cloud-init target. [ 86.230432] ACPI CPPC: PCC check channel failed. Status=0 [ 86.701943] ACPI CPPC: PCC check channel failed. Status=0 [ 86.773668] ACPI CPPC: PCC check channel failed. Status=0 [ 87.369958] ACPI CPPC: PCC check channel failed. Status=0 [ 87.733361] ACPI CPPC: PCC check channel failed. Status=0 [ 88.207372] ACPI CPPC: PCC check channel failed. Status=0 ubuntu@starbuck:~$ uname -a Linux starbuck 4.15.0-13-generic #14-Ubuntu SMP Sat Mar 17 13:44:36 UTC 2018 aarch64 aarch64 aarch64 GNU/Linux -- after kernel patch -- OK ] Started Apply the settings specified in cloud-config. Starting Execute cloud user/final scripts... [ 67.178425] cloud-init[3688]: Cloud-init v. 18.2 running 'modules:final' at Fri, 13 Apr 2018 20:41:15 +. Up 65.98 seconds. [ 67.200190] cloud-init[3688]: Cloud-init v. 18.2 finished at Fri, 13 Apr 2018 20:41:15 +. Datasource DataSourceMAAS [http://10.228.68.5:5240/MAAS/metadata/]. Up 66.83 seconds [ OK ] Started Execute cloud user/final scripts. [ OK ] Reached target Cloud-init target. Ubuntu Bionic Beaver (development branch) starbuck ttyAMA0 starbuck login: ubuntu@starbuck:~$ uname -a Linux starbuck 4.15.0-15-generic #16~lp1763817+build.1 SMP Fri Apr 13 19:54:10 UTC 2018 aarch64 aarch64 aarch64 GNU/Linux [Regression Potential] None. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1763817/+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
[Kernel-packages] [Bug 1392176] Re: mounts cgroups unconditionally which causes undesired effects with cpu hotplug
FYI: My use case for hot plugging my x86 system like a drunken sailor is to evaluate the amount of CPUs required to complete a given task before I schedule it to run on other potentially CPU bound machines. -- 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/1392176 Title: mounts cgroups unconditionally which causes undesired effects with cpu hotplug Status in cgmanager package in Ubuntu: Confirmed Status in linux package in Ubuntu: Confirmed Status in systemd package in Ubuntu: Incomplete Bug description: == Comment: #0 - Preeti U. Murthy - 2014-10-20 04:40:12 == ---Problem Description--- Systemd mounts cgroups explicitly every boot. Since the user had no say in it, undesired consequences are observed in reaction to cpu hotplug operations. Here is how. Systemd moves the tasks to the cgroup mounted by it. This cgroup automatically becomes the child of the root cgroup which is present by default. The children cgroups are not expected to remember their configured cpusets after hotplug operations in the kernel. Hence when cpus are taken offline and brought back online they are no longer used for load balancing of tasks and hence remain unused. This is an undesired consequence because the user had not even asked for cgroups to be mounted, yet is not able to use the full capacity of the system. Only when the user himself creates cgroup hierarchies, should he be exposed to the side effects of cpu hotplug on cpusets. Else all online cpus must be made available to him which is not happening since systemd mounts cgroups on every boot. Hence please revert this feature or provide an explaination as to why this is being done. ---uname output--- Linux tul181p1 3.16.0-18-generic #25-Ubuntu SMP Fri Sep 26 02:39:53 UTC 2014 ppc64le ppc64le ppc64le GNU/Linux Machine Type = Tuleta 8286-42A ---Debugger--- A debugger was configured, however the system did not enter into the debugger ---Steps to Reproduce--- $ taskset -p $$ $ 0-127 $ echo 0 > /sys/devices/system/cpu/cpu7/online $ taskset -p $$ $ 0-6,8-127 $ echo 1 > /sys/devices/system/cpu/cpu7/online $ taskset -p $$ $ 0-6,8-127 Userspace tool common name: systemd The userspace tool has the following bit modes: 64-bit Userspace rpm: systemd_208-8ubuntu8_ppc64el.deb Userspace tool obtained from project website: 208-8ubuntu8 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/cgmanager/+bug/1392176/+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
