------- Comment From [email protected] 2018-09-05 05:06 EDT------- (In reply to comment #8) > @IBM: Even if we do not have NVMe devices in our Z machine (hence we cannot > test this on s390x by ourselves) it would be good and helpful if you can > share a description / or some steps of a potential test case. > This would help judging the regression risk in case of an SRU to 18.04 (and > is needed for a SRU anyway).
The trigger is a PCI function whose driver requests more interrupts than the architectural maximum. Currently this is only possible with a machine that supports 64 CPUs (or more) with a NVMe function attached. Note that the LPAR does not have to use >=64 CPUs since the NVMe driver uses num_possible_cpus() which is resolved to the machine maximum on s390 (since all CPUs are hot-pluggable). The oops happens after the driver calls pci_alloc_irq_vectors during device probing - so most likely the system will panic during boot. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1790480 Title: random oopses on s390 systems using NVMe devices To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-z-systems/+bug/1790480/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
