perf top problem on z with Ubuntu 18.04
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
Ubuntu on IBM z Systems |
Fix Released
|
High
|
Canonical Kernel Team | ||
linux (Ubuntu) |
Fix Released
|
Undecided
|
Skipper Bug Screeners | ||
Bionic |
Fix Released
|
High
|
Unassigned | ||
Cosmic |
Invalid
|
Undecided
|
Unassigned | ||
Disco |
Fix Released
|
High
|
Unassigned |
Bug Description
SRU Justification:
==================
[Impact]
* The perf top tool hangs and shows error messages, like 'Not enough memory for annotating'
[Fix]
* b9c0a64901d5bde
* 12a6d2940b5f02b
Disco needs also as prereq:
* 6738028dd57df06
[Test Case]
* start a benchmark (mem_alloc, but it doesn't really matter what)
* execute perf top in a second terminal
* the output of perf top is correct
* now stop the benchmark
* and perf top shows an error message, like "Not enough memory for annotating '__irf_end' symbol!)"
* and perf top can't be exited anymore
[Regression Potential]
* The regression potential can be considered as medium since this happens only while using the perf top tool
* and just 3 files are changed, and one of them is arch/s390/
* but symbol and machine header in /tools/perf/util modified and several loc added
[Other Info]
* cherry-pick was possible to bionic-master-next and to disco-master-next (but used '--strategy=
* adding the patches to disco is to avoid regressions
_______
perf top hangs and shows error messages
---uname output---
Linux weather 4.15.0-46-generic #49-Ubuntu SMP Wed Feb 6 09:32:27 UTC 2019 s390x s390x s390x GNU/Linux
---Steps to Reproduce---
I start a benchmark (mem_alloc, but it really doesn't matter) and then issue perf top in a second terminal, the output from perf top is correct. Now I stop the benchmark: perf top shows a error message (Not enough memory for annotating '__irf_end' symbol!) and I can't quit from perf top anymore
Following analyse took place:
No problem with current kernel .
Bi-Secting of perf tool took place and following commit was found:
commit edeb0c90df3581b
Author: Arnaldo Carvalho de Melo <email address hidden>
Date: Tue Oct 16 17:08:29 2018 -0300
perf tools: Stop fallbacking to kallsyms for vdso symbols lookup
When you apply this patch the issue is gone, however it is contained in these versions:
git tag --contains edeb0c90df3581b821
v4.19
v4.20
....
The level I was debugging was kernel 4.15 which does not contain this patch.
description: | updated |
Changed in linux (Ubuntu): | |
status: | New → Fix Released |
Changed in linux (Ubuntu Bionic): | |
status: | New → In Progress |
Changed in linux (Ubuntu Cosmic): | |
status: | New → In Progress |
Changed in ubuntu-z-systems: | |
status: | Triaged → In Progress |
Changed in ubuntu-z-systems: | |
status: | Incomplete → Triaged |
Changed in linux (Ubuntu): | |
status: | Fix Released → Confirmed |
Changed in linux (Ubuntu Cosmic): | |
status: | In Progress → Invalid |
Changed in ubuntu-z-systems: | |
status: | Incomplete → Triaged |
Changed in linux (Ubuntu Disco): | |
status: | New → In Progress |
Changed in linux (Ubuntu Bionic): | |
importance: | Undecided → High |
Changed in linux (Ubuntu Disco): | |
importance: | Undecided → High |
Changed in ubuntu-z-systems: | |
status: | Triaged → In Progress |
description: | updated |
Changed in ubuntu-z-systems: | |
status: | In Progress → Fix Committed |
description: | updated |
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