Comment 16 for bug 1569468

ok, no worries. Let me know and I'll retest that too, if needed.

On Tue, Apr 26, 2016 at 2:59 PM, Colin Ian King
<email address hidden> wrote:
> Thanks for testing, however, I found a regression in one of the other
> bugs being fixed by this update, so we're waiting for the -1ubuntu2
> release to land in -proposed for final testing.
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1569468
>
> Title:
> stress-ng mmap failing on zVM and LPAR
>
> Status in stress-ng package in Ubuntu:
> Fix Committed
> Status in stress-ng source package in Xenial:
> Fix Committed
>
> Bug description:
> [SRU, Xenial]
>
> When running stress-ng on zVM and LPAR we are hitting SIGBUS errors
> because we have a sparsely allocated mmap'd backing file which due to
> over commit and a full file system causes pages not to be mapped in
> and causes memory accesses on unbacked pages to trigger a SIGBUS.
>
> [REPRODUCER + FIX]
> Run stress-ng --mmap 64 --maximize on a filesystem that is very nearly full and the SIGBUS triggers and the stressor exits early with SIGBUS. With the fix, the SIGBUS is caught and the stressor can continue without premature early exit.
>
> [REGRESSION POTENTIAL]
> I am requesting syncing with 0.05.24 micro release as this contains the fix plus a few SIGSEGV stack trapping fixes. stress-ng is a universe leaf project and the fixes touch just a few of the stress tests. These have been regression checked on various architectures and the code passes static analysis on cppcheck, CoverityScan and clang's scan-build, so regression potential is minimal.
>
>
> --------------------------------------------------------------------------
>
> Running stress-ng on s390 in all three modes. This seems to work ok
> in z/KVM, however, on zVM and LPAR as of a few days ago on Xenial the
> mmap stressor has started failing.
>
> I tried to get detailed logs but either don't know the correct
> switches or they simply aren't there.
>
> Here is the output when I used --log-file and --verbose on an LPAR:
> root@s1lp10-jefflane:~# less stress-ng-mmap-fail.log
> stress-ng: debug: [179421] 4 processors online, 4 processors configured
> stress-ng: info: [179421] dispatching hogs: 4 mmap
> stress-ng: debug: [179421] cache allocate: reducing cache level from L3 (too high) to L2
> stress-ng: info: [179421] cache allocate: default cache size: 2048K
> stress-ng: debug: [179421] starting stressors
> stress-ng: debug: [179422] stress-ng-mmap: started [179422] (instance 0)
> stress-ng: debug: [179423] stress-ng-mmap: started [179423] (instance 1)
> stress-ng: debug: [179424] stress-ng-mmap: started [179424] (instance 2)
> stress-ng: debug: [179421] 4 stressors spawned
> stress-ng: debug: [179425] stress-ng-mmap: started [179425] (instance 3)
> stress-ng: debug: [179424] stress-ng-mmap: exited [179424] (instance 2)
> stress-ng: debug: [179422] stress-ng-mmap: exited [179422] (instance 0)
> stress-ng: debug: [179421] process [179422] terminated
> stress-ng: debug: [179421] process 179423 (stress-ng-mmap) terminated on signal: 7 (Bus error)
> stress-ng: debug: [179421] process [179423] terminated
> stress-ng: debug: [179421] process [179424] terminated
> stress-ng: debug: [179421] process 179425 (stress-ng-mmap) terminated on signal: 7 (Bus error)
> stress-ng: debug: [179421] process [179425] terminated
> stress-ng: info: [179421] unsuccessful run completed in 300.68s (5 mins, 0.68 secs)
>
> That is the only info I have for the failure, unfortunately.
>
> ProblemType: Bug
> DistroRelease: Ubuntu 16.04
> Package: stress-ng 0.05.23-1
> ProcVersionSignature: Ubuntu 4.4.0-18.34-generic 4.4.6
> Uname: Linux 4.4.0-18-generic s390x
> ApportVersion: 2.20.1-0ubuntu1
> Architecture: s390x
> Date: Tue Apr 12 12:47:49 2016
> ProcEnviron:
> TERM=screen
> PATH=(custom, no user)
> XDG_RUNTIME_DIR=<set>
> LANG=en_US.UTF-8
> SHELL=/bin/bash
> SourcePackage: stress-ng
> UpgradeStatus: No upgrade log present (probably fresh install)
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/ubuntu/+source/stress-ng/+bug/1569468/+subscriptions
>
> Launchpad-Notification-Type: bug
> Launchpad-Bug: distribution=ubuntu; sourcepackage=stress-ng; component=universe; status=Fix Committed; importance=High; <email address hidden>;
> Launchpad-Bug: distribution=ubuntu; distroseries=xenial; sourcepackage=stress-ng; component=universe; status=Fix Committed; importance=High; <email address hidden>;
> Launchpad-Bug-Tags: apport-bug blocks-hwcert-server s390x verification-needed xenial
> Launchpad-Bug-Information-Type: Public
> Launchpad-Bug-Private: no
> Launchpad-Bug-Security-Vulnerability: no
> Launchpad-Bug-Commenters: bladernr colin-king pitti
> Launchpad-Bug-Reporter: Jeff Lane (bladernr)
> Launchpad-Bug-Modifier: Colin Ian King (colin-king)
> Launchpad-Message-Rationale: Subscriber
> Launchpad-Message-For: bladernr

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