So the root issue behind this was stress-ng was calling prctl(PR_SET_DUMPABLE) which causes the oom-adjustments to not be set. This in turn meant that running the sockpair stressor as root let do non-oomable processes when memory got tight and we end up in locked in kernel space looking for free pages to create a socket pair.
This is a kind of DoS, however, it is running as root on a low memory i386 system, so I'm currently fixing the stress-ng oom-adjustments issue so at least the kernel can OOM the stressor. I've also added oom detecting in the stressor and auto-respawning to keep the pressure up when a process gets killed. See commits: http://kernel.ubuntu.com/git/cking/stress-ng.git/commit/?id=4e098f94e6366bf096506d8c78fd9f96a0a59950 http://kernel.ubuntu.com/git/cking/stress-ng.git/commit/?id=47eb86ed8e13bd9171672f7b5b98773452e4fd16 ** Changed in: linux (Ubuntu) Status: In Progress => Fix Committed -- 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/1654971 Title: linux 4.4.0-59.80 ADT test failure with linux 4.4.0-59.80 Status in linux package in Ubuntu: Fix Committed Bug description: Testing failed on: i386: https://objectstorage.prodstack4-5.canonical.com/v1/AUTH_77e2ada1e7a84929a74ba3b87153c0ac/autopkgtest-xenial/xenial/i386/l/linux/20170109_080549_35691@/log.gz To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1654971/+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
