** Description changed: + == SRU justification [Xenial, Bionic] == + + Running blktrace on systems where CPUs are offlined such that: + + 1. sysconf(_SC_NPROCESSORS_ONLN) < sysconf(_SC_NPROCESSORS_CONF) and/or + 2. CPU 0..sysconf(_SC_NPROCESSORS_ONLN) - 1 is offline + + ..causes blktrace to fail with an error such as: + + FAILED to start thread on CPU 156: 22/Invalid argument + FAILED to start thread on CPU 157: 22/Invalid argument + FAILED to start thread on CPU 158: 22/Invalid argument + .. + etc + + == Test case == + + Run blktrace on a system that has sysconf(_SC_NPROCESSORS_ONLN) < + sysconf(_SC_NPROCESSORS_CONF). It will break with the invalid argument + error for sysconf(_SC_NPROCESSORS_ONLN) <= CPU < + sysconf(_SC_NPROCESSORS_ONLN). + + With the fix, blktrace on these systems will work find and the ubuntu + blktrace regresssion test will also pass. + + == The Fix(es) == + + commit 80c4041b2e7a7d5afb75df563bf51bb27773c095 + Author: Abutalib Aghayev <[email protected]> + Date: Tue Feb 9 08:17:50 2016 -0700 + + blktrace: Use number of online CPUs + + the above fix addresses the case where the number of online cpus is less + than the number of cpus configured. + + commit d045a704a378b9041ebe3d60c497a5656a79d439 + Author: Jan Kara <[email protected]> + Date: Thu Jan 26 11:23:53 2017 +0100 + + blktrace: Add support for sparse CPU numbers + + the above commit fixes the case where one or more CPUs + 0..sysconf(_SC_NPROCESSORS_ONLN) is offline causing sparse CPU + numbering. + + == Regression Potential == + + Small, the fixes have been in blktrace since 2017 and have had no + subsequent fixes so the fixes look stable. The fixes are designed to + fix this specific issue as seen in the bug. The fixes adjust the number + of CPUs accounted for by blktrace; at worst the fixes could break + blktrace. + + + ---------------- + This issue could be found on 4.15 / 4.18 / 5.0 Bionic. Investigation show this was caused by a CPU offline issue for this node "baltar" (bug 1827335) and can be reproduced on another P9 node "bobone" Combined with the issue to the blktrace itself, (Upstream bug for blktrace attempting to operate on offline CPUs: https://bugzilla.redhat.com/show_bug.cgi?id=1321875) the test failed. $ sudo ./ubuntu_blktrace_smoke_test.sh PASSED (CONFIG_BLK_DEV_IO_TRACE=y in /boot/config-4.15.0-48-generic) Using block device /dev/loop0 for path /home/ubuntu/autotest-client- tests/ubuntu_blktrace_smoke_test/mnt Test regime: dd performing 65536 1K block writes looking for at least 1024 blktrace events Thu May 2 03:45:41 UTC 2019: blktrace starting Thu May 2 03:45:41 UTC 2019: dd starting FAILED to start thread on CPU 156: 22/Invalid argument FAILED to start thread on CPU 157: 22/Invalid argument FAILED to start thread on CPU 158: 22/Invalid argument FAILED to start thread on CPU 159: 22/Invalid argument Thu May 2 03:45:45 UTC 2019: dd stopped Thu May 2 03:45:45 UTC 2019: waiting for 10 seconds Thu May 2 03:45:55 UTC 2019: blktrace being terminated Thu May 2 03:45:55 UTC 2019: blktrace terminated Thu May 2 03:45:56 UTC 2019: blktrace data parsed ./ubuntu_blktrace_smoke_test.sh: line 237: [: -eq: unary operator expected ./ubuntu_blktrace_smoke_test.sh: line 240: [: -eq: unary operator expected FAILED (expecting at least 1024 block traces events from the dd process, got 0) FAILED (expecting at least 1024 block read traces events, got 0) FAILED (expecting at least 1024 block write traces events, got 0) Summary: 1 passed, 3 failed
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1827318 Title: ubuntu_blktrace_smoke_test failed on Bionic P9 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-kernel-tests/+bug/1827318/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
