This 128M value is adequate for almost all configurations. There must be something specific about HyperV configurations that makes 256M a requirement.
I don't think that the value should be raised for only that one exception. We should identify why 256M is required though -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to kexec-tools in Ubuntu. https://bugs.launchpad.net/bugs/1359980 Title: [Hyper-V] Unable to perform a full kernel crash on Ubuntu 14.10 Status in kexec-tools package in Ubuntu: New Status in kexec-tools source package in Utopic: New Bug description: System details: Linux ubuntu 3.16.0-9-generic #14-Ubuntu SMP Fri Aug 15 15:03:57 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux Ubuntu Server 14.10 Daily build from 19th Aug (first build picked up for testing) We have followed the steps at https://wiki.ubuntu.com/Kernel/CrashdumpRecipe to configure kdump on a Generation 1 VM. kdump is loaded and when we trigger the crash, a kernel panic is displayed. Issues: 1. The vmcore/crash file is not generated under /var/crash as configured in the kdump config. 2. The VM will hang and not reboot. Default action to take in case of a failure is to reboot - again as set in kdump config. Repro rate: 100% VM settings: tests ran with 1 CPU core or 4 cores. Negociated VMBus is 3.0, which has been integrated since 14.04 so this should work as no other patches are needed. (https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1317697) I'm also attaching the serial console output of both cases - single core and SMP. root@ubuntu:~# kdump-config load efi memory descriptor version 0 is not supported! * loaded kdump kernel root@ubuntu:~# cat /sys/kernel/kexec_crash_loaded 1 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/kexec-tools/+bug/1359980/+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
