| 2018-10-10 18:36:24 |
Manoj Iyer |
bug |
|
|
added bug |
| 2018-10-10 18:36:31 |
Manoj Iyer |
nominated for series |
|
Ubuntu Bionic |
|
| 2018-10-10 19:00:17 |
Ubuntu Kernel Bot |
linux (Ubuntu): status |
New |
Incomplete |
|
| 2018-10-10 19:00:18 |
Ubuntu Kernel Bot |
tags |
cavium |
bionic cavium |
|
| 2018-10-11 21:29:06 |
Manoj Iyer |
description |
[Impact]
The numa mask subset check can often lead to system hang or crash during CPU hotplug and system suspend operation if NUMA is disabled. This is mostly observed on HMP systems where the CPU compute capacities are different and ends up in different scheduler domains. Since cpumask_of_node is returned instead core_sibling, the scheduler is confused with incorrect cpumasks(e.g. one CPU in two different sched domains at the same time) on CPU hotplug.
[Fix]
The following patch fixes this issue:
e156ab71a974 arm64: topology: Avoid checking numa mask for scheduler MC selection
[Test]
[Regression Potential] |
[Impact]
The numa mask subset check can often lead to system hang or crash during CPU hotplug and system suspend operation if NUMA is disabled. This is mostly observed on HMP systems where the CPU compute capacities are different and ends up in different scheduler domains. Since cpumask_of_node is returned instead core_sibling, the scheduler is confused with incorrect cpumasks(e.g. one CPU in two different sched domains at the same time) on CPU hotplug.
[Fix]
The following patch fixes this issue:
e156ab71a974 arm64: topology: Avoid checking numa mask for scheduler MC selection
[Test]
-- testcase --
#!/bin/bash
stress-ng -q --vm 100 --vm-bytes 1G --cpu 210 --timeout 2400s --metrics-brief &
pid=$!
for i in {1..210}; do
num=$((RANDOM%10+$i))
echo "Offline CPU $num"
echo 0 > /sys/devices/system/cpu/cpu$num/online || exit 1
sleep 3s
echo "Online CPU $num"
echo 1 > /sys/devices/system/cpu/cpu$num/online || exit 1
done
kill -9 $pid
----------------
Executed the test case with stock Bionic kernel and with Bionic kernel with patches applied. No system hang or crash was observed. On Cavium CN99XX Thunder X2 system.
[Regression Potential]
Regression tested on Cavium Thunder X2 CN99XX system, and none were found. Regression risk is low. |
|
| 2018-10-15 10:08:25 |
Kleber Sacilotto de Souza |
bug task added |
|
linux (Ubuntu Bionic) |
|
| 2018-10-15 10:08:30 |
Kleber Sacilotto de Souza |
linux (Ubuntu Bionic): status |
New |
In Progress |
|
| 2018-10-15 10:08:33 |
Kleber Sacilotto de Souza |
linux (Ubuntu): status |
Incomplete |
Invalid |
|
| 2018-10-23 14:47:18 |
Kleber Sacilotto de Souza |
linux (Ubuntu Bionic): status |
In Progress |
Fix Committed |
|
| 2018-10-24 13:35:35 |
Brad Figg |
tags |
bionic cavium |
bionic cavium verification-needed-bionic |
|
| 2018-10-29 17:08:04 |
Manoj Iyer |
tags |
bionic cavium verification-needed-bionic |
bionic cavium verification-done-bionic |
|
| 2018-11-13 18:51:26 |
Launchpad Janitor |
linux (Ubuntu Bionic): status |
Fix Committed |
Fix Released |
|
| 2018-11-13 18:51:26 |
Launchpad Janitor |
cve linked |
|
2017-13168 |
|
| 2018-11-13 18:51:26 |
Launchpad Janitor |
cve linked |
|
2018-15471 |
|
| 2018-11-13 18:51:26 |
Launchpad Janitor |
cve linked |
|
2018-16658 |
|
| 2018-11-13 18:51:26 |
Launchpad Janitor |
cve linked |
|
2018-9363 |
|
| 2019-07-24 21:28:22 |
Brad Figg |
tags |
bionic cavium verification-done-bionic |
bionic cavium cscc verification-done-bionic |
|
