kernel-packages team mailing list archive

[Stefan Bader <stefan.bader@xxxxxxxxxxxxx>]

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.

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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

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