The first kernel on that list that exhibits the bug is the first one: 4.14 Final. Recall: the bug results in a full up hang. The disk stops swapping (it's audible). I can reboot with sysctl SUB however.
I then tested 4.13.0-36 from the Ubuntu 17.10 respoitory, followed by 4.11.12-041112-generic from mainline. Both had the bug. I also tested each of these without cryptswap (i.e. normal swap) and they did not hang. The system ground to a halt, but I could hear the disk swapping and the process eventually completed. I then booted an 16.04 live usb which has kernel 4.10. I had to make a cryptswap using cryptsetup on the swap partition of the hard disk, to test it. But this one worked! The behavior was a bit different that more recent kernels: after allocating 6 GB of the 10 GB that I requested, the system invoked the oom-killer on the process. However, it did not hang. I then grabbed 4.10.1-041001-generic from mainline and tested it. This worked the same as the live usb. So 4.10 does not have the bug, although the oom-killer is invoked to kill the process grabbing the memory. I have an older machine with an SSD. This does not exhibit the bug on Ubuntu 17.10 running 4.13.0-36. However, this disk is _fast_ (Samsung EVO), so I'm guessing that there is some tuning problem, maybe, in how the kernel handles swap speed vs memory allocation requests??? I really don't know. --M On 04/11/2018 11:18 AM, Joseph Salisbury wrote: > I'd like to perform a bisect to figure out what commit caused this > regression. We need to identify the earliest kernel where the issue > started happening as well as the latest kernel that did not have this > issue. > > Can you test the following kernels and report back? We are looking for > the first kernel version that exhibits this bug: > > v4.14 Final: http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.14/ > v4.15-rc1: http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.15-rc1/ > v4.15-rc4: http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.15-rc4/ > v4.15 Final: http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.15/ > > You don't have to test every kernel, just up until the kernel that first > has this bug. > > Thanks in advance! > > ** Tags added: performing-bisect > -- Martin Weinberg 6 Grass Hill Rd West Whately, MA 010039 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1762468 Title: Cryptoswap not working in Bionic To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1762468/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
