linux - Memory Bandwidth Monitoring regression
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux (Ubuntu) |
Fix Released
|
Undecided
|
Unassigned | ||
Xenial |
Fix Released
|
Undecided
|
Tim Gardner |
Bug Description
Hi team,,
I have a customer, who tried to install Xenial or upgrade to 4.4 kernel with Trusty on our cloud platform(qemu 1.5.3), reports a defect. he complains that only one cpu is successfully detected, other cpus is disabled if
he used 4.4 kernel. I tried to bisect Xenial kernel tree, and found that this bug was introduced by the following commit.
commit 31c2013e4ea2e59
Author: Thomas Gleixner <email address hidden>
Date: Mon Feb 22 22:19:15 2016 +0000
x86/topology: Create logical package id
BugLink: http://
For per package oriented services we must be able to rely on the number of CPU
packages to be within bounds. Create a tracking facility, which
- calculates the number of possible packages depending on nr_cpu_ids after boot
- makes sure that the package id is within the number of possible packages. If
the apic id is outside we map it to a logical package id if there is enough
space available.
Provide interfaces for drivers to query the mapping and do translations from
physcial to logical ids.
and then I backported 7b0501b1e7cddd3
From 7b0501b1e7cddd3
From: Jiri Olsa <email address hidden>
Date: Mon, 15 Aug 2016 12:17:00 +0200
Subject: [PATCH] x86/smp: Fix __max_logical_
Frank reported kernel panic when he disabled several cores in BIOS
via following option:
Thanks
Wei
Changed in linux (Ubuntu Xenial): | |
status: | In Progress → Fix Committed |
Changed in linux (Ubuntu Xenial): | |
status: | Fix Committed → Fix Released |
https:/ /lists. ubuntu. com/archives/ kernel- team/2016- December/ 081278. html