I wonder how AWS manages to get that odd (literally) number of CPUs. >From the dmesg:
smpboot: Allowing 15 CPUs, 13 hotplug CPUs >From that it looks like possible=15 and num_processors=2 in prefill_possible_,map(). And possible is assigned to nr_cpu_ids after printing the line above. Confirmed in dmesg a little down: setup_percpu: NR_CPUS:256 nr_cpumask_bits:256 nr_cpu_ids:15 nr_node_ids:1 The divide error is in smp_init_package_map() which is inlined from smp_store_boot_cpu_info(). This would print "Max logical packages: ..." at some point which is not in dmesg. The only places there that look like they could cause a divide by 0 would be using ncpus. The first instance here: ncpus = boot_cpu_data.x86_max_cores; __max_logical_packages = DIV_ROUND_UP(total_cpus, ncpus); Have not yet dug down into where x86_max_cores gets set. -- 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/1582776 Title: HVM/SSD Xenial AWS AMI doesn't launch on r3.large Status in linux package in Ubuntu: Confirmed Status in linux source package in Xenial: Confirmed Bug description: **NOTE** The additional information attached to this bug report is for my laptop and does not apply to this bug report. Using ubuntu-bug, I'm not sure how to control this. Using the debian bug tool, I would have just edited the file.... If you attempt to launch an ec2 instance using IMAGE ami-c1cb23ac 099720109477/ubuntu/images-testing/hvm-ssd /ubuntu-xenial-daily-amd64-server-20160516.1 099720109477 available public x86_64 machine on an instance of type r3.large, the kernel doesn't boot. You get output such as the attached log (kernel-ami-c1cb23ac.log). You get essentially the same result if you try to launch an image from ami-840910ee which is the AMI you get from http://cloud- images.ubuntu.com/locator/ with the search string "16.04 hvm us-east ssd" and picking the latest version. HVM is supposed to work on r3.large. We have used this successfully with Ubuntu 12.04, 14.04, and 15.10 and also with CentOS 5, 6, and 7. r3.large is supposed to work with both HVM and PV. We have no problems with this AMI on m4 or c4 instances which only support HVM. ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: linux-image-4.4.0-22-generic 4.4.0-22.40 ProcVersionSignature: Ubuntu 4.4.0-22.39-generic 4.4.8 Uname: Linux 4.4.0-22-generic x86_64 ApportVersion: 2.20.1-0ubuntu2 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: ejb 14140 F.... pulseaudio Date: Tue May 17 11:06:11 2016 HibernationDevice: RESUME=UUID=1c991c18-29ed-4f63-b481-89ef40b91b94 InstallationDate: Installed on 2016-04-22 (24 days ago) InstallationMedia: Xubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1) IwConfig: docker0 no wireless extensions. enp0s3 no wireless extensions. lo no wireless extensions. Lsusb: Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 001 Device 002: ID 80ee:0021 VirtualBox USB Tablet Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub MachineType: innotek GmbH VirtualBox ProcFB: 0 vboxdrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-22-generic root=/dev/mapper/jblin0-root_16_04 ro quiet splash RelatedPackageVersions: linux-restricted-modules-4.4.0-22-generic N/A linux-backports-modules-4.4.0-22-generic N/A linux-firmware 1.157 RfKill: SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 12/01/2006 dmi.bios.vendor: innotek GmbH dmi.bios.version: VirtualBox dmi.board.name: VirtualBox dmi.board.vendor: Oracle Corporation dmi.board.version: 1.2 dmi.chassis.type: 1 dmi.chassis.vendor: Oracle Corporation dmi.modalias: dmi:bvninnotekGmbH:bvrVirtualBox:bd12/01/2006:svninnotekGmbH:pnVirtualBox:pvr1.2:rvnOracleCorporation:rnVirtualBox:rvr1.2:cvnOracleCorporation:ct1:cvr: dmi.product.name: VirtualBox dmi.product.version: 1.2 dmi.sys.vendor: innotek GmbH To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1582776/+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
