Ahhh, ok. Thanks. That makes sense, then. On Fri, Nov 16, 2018 at 12:01 AM Joseph Salisbury wrote: > > The Xenial bug task is for the base Xenial kernel version 4.4. Any > commits/fixes applied to Bionic flow down into Xenial HWE because Bionic > is 4.15 based, which is the source for Xenial HWE. > > -- > You received this bug notification because you are subscribed to the bug > report. > https://bugs.launchpad.net/bugs/1798127 > > Title: > CPU Soft Lockups when stress-ng stack stressor runs with M.2 NVMe as > root FS > > Status in linux package in Ubuntu: > Triaged > Status in linux source package in Xenial: > Invalid > Status in linux source package in Bionic: > Triaged > Status in linux source package in Cosmic: > Triaged > > Bug description: > This was reported by a hardware partner. The system set up is a > server with 512GB RAM and an M.2 NVMe drive as the root > filesystem/boot device. > > Per the customer, when running the certification Memory Stress test > (utilizing several stress-ng stressors run in sequence) the system > freezes with CPU Soft Lockup errors appearing on console whe the > "stack" stressor is run. > > Tester has tried with 2.5” SATA (1TB), 2.5” NVMe (800GB), and M.2 NVMe > (1.9TB). > > So far, this only seems to affect the 4.15 kernel. The tester has > tried using the 2.5" SATA SSD as the RootFS/Boot device and the tests > pass on all attempts. It is ONLY when using the M.2 NVMe as the root > / boot device that the tests cause a lockup. The tester is re-trying > now with the 2.5" NVMe device to see if this only occurs with the M.2 > NVMe. > > The tester has tried this on the following while using the M.2 NVMe as the rootFS/Boot device: > Test run #1 – 16.04.5 at kernel 4.15; Result: Failed stress-ng memory on stack stressor > Test run #2 – 18.04.1 at kernel 4.15; Result: Failed stress-ng memory on stack stressor > Test run #3 – 16.04.5 at kernel 4.4; Result: Passed stress-ng memory test > > The stress-ng command invoked at the time the soft lockups occur is > this: > > 'stress-ng -k --aggressive --verify --timeout 300 --stack 0' > > This can be reproduced by running the memory_stress_ng test script > from the cert suite: > > sudo /usr/lib/plainbox-provider-certification- > server/bin/memory_stress_ng > > It may be more easily reproducible running the stack stressor alone, > or the whole memory stress script without dealing with Checkbox. > > UPDATE: The tester also confirms that the 2.5" NVMe drives also fail > with the 4.15 kernel and pass with the 4.4 kernel. The SSD works on > all kernels. > > To manage notifications about this bug go to: > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1798127/+subscriptions > > Launchpad-Notification-Type: bug > Launchpad-Bug: distribution=ubuntu; sourcepackage=linux; component=main; status=Triaged; importance=High;