------- Comment From tmri...@de.ibm.com 2019-07-19 07:37 EDT------- Thanks for your help.
I have installed root@s8360046:~/linux-4.15.0/tools/perf# uname -a Linux s8360046 4.15.0-54-generic #58-Ubuntu SMP Mon Jun 24 10:54:05 UTC 2019 s390x s390x s390x GNU/Linux root@s8360046:~/linux-4.15.0/tools/perf# and download the corresponding linux kernel source tree from us.ports/ubuntu.com. So the linux kernel I am using matches the sources and I built the perf tool. I can also recreate the issue and I start debugging this issue. -- 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/1828166 Title: perf top problem on z with Ubuntu 18.04 Status in Ubuntu on IBM z Systems: Confirmed Status in linux package in Ubuntu: Confirmed Status in linux source package in Bionic: In Progress Status in linux source package in Cosmic: Invalid Bug description: SRU Justification: ================== [Impact] * The perf top tool hangs and shows error messages, like 'Not enough memory for annotating' [Fix] * edeb0c90df3581b821a764052d185df985f8b8dc edeb0c9 "perf tools: Stop fallbacking to kallsyms for vdso symbols lookup" [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 low since this happens only while using the perf top tool * and it is known that the commit (above) fixes the problem * and the fix is upstream since 4.19 [Other Info] * current disco and eoan kernels don't show that problem * bisecting result points to above commit * applies cleanly on cosmic, but has a little conflict on bionic (both master-next) _________________________ 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 edeb0c90df3581b821a764052d185df985f8b8dc (HEAD, refs/bisect/bad) Author: Arnaldo Carvalho de Melo <a...@redhat.com> 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. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-z-systems/+bug/1828166/+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
