Re: [Qemu-devel] [Bug 1769053] Re: Cannot start a guest with more than 1TB of RAM

[Daniel Axtens <daniel.axtens@canonical.com>]

Hi Christian,

Sorry, I should have been a *lot* more clear.

I wanted to file the bug so that we have somewhere to figure out what needs
to be done and track the progress - trying to avoid it becoming something
we vaguely know about but don't ever do anything about.

Thanks so much for your analysis of the patches. I will dig in to the
upstream status and see where they're at with large memory guests.

I know we're missing test hardware. I will make some enquiries within the
team and see what can dig up, otherwise we have a customer that might be
able to run some tests.

So for now, the action items are:
 - I will hunt down a >1TB machine.
 - I will check what the progress of 1TB guests in upstream Qemu is.

Apologies again, and thanks for the pointers.

Regards,
Daniel

On Fri, May 4, 2018 at 5:44 PM, ChristianEhrhardt <
1769053@bugs.launchpad.net> wrote:

> Hi Daniel,
> might I ask what you expect now?
>
> The changes to seabios are not even upstream yet in git://
> git.seabios.org/seabios.git
> The changes to qemu are neither upstream in git://git.qemu.org/qemu.git
>
> The changes linked also are for a qemu way++ back in time (like pre
> trusty), so they just don't apply. Some of these changes are handled
> already, but different like the second qemu change of above mail is in qemu
> since "6c7c3c21 x86: implement la57 paging mode" which is qemu >=2.9.
> That said - this one I could track, maybe the other changes are also
> upstream but in a way different form.
>
> At least for myself I currently have no >1TB system to even try this -
> well I have done this on s390x and there it works fine already but you
> need x86 here.
>
> Even when all of the above would be resolved, the mail above states that
> even if those are applied they still have issues when going >1TB.
>
> I think you'd need a clear this is what I tried and this is what fails
> with a setup as simple as possible. If it fails in Ubuntu we can build a
> latest upstream build for you and if failing there we can work with
> upstream to resolve properly. From there we can think about the
> backportability of those changes. But the suggested "hey there are these
> patches, won't work.
>
> Please don't get me wrong (I want to help), but so far this appears to me
> so far as a suggestion of a set of non-upstreamed, non-applicable,
> non-testable, non-working changes.
> We need to better sort out how to handle this which is why I ask what you
> expect to happen now.
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1769053
>
> Title:
>   Cannot start a guest with more than 1TB of RAM
>
> Status in QEMU:
>   New
> Status in qemu package in Ubuntu:
>   New
>
> Bug description:
>   Attempting to start a KVM guest with more than 1TB of RAM fails.
>
>   It looks like we might need some extra patches:
>   https://lists.gnu.org/archive/html/qemu-discuss/2017-12/msg00005.html
>
>   ProblemType: Bug
>   DistroRelease: Ubuntu 18.04
>   Package: qemu-system-x86 1:2.11+dfsg-1ubuntu7
>   ProcVersionSignature: Ubuntu 4.15.0-20.21-generic 4.15.17
>   Uname: Linux 4.15.0-20-generic x86_64
>   ApportVersion: 2.20.9-0ubuntu7
>   Architecture: amd64
>   CurrentDesktop: Unity:Unity7:ubuntu
>   Date: Fri May  4 16:21:14 2018
>   InstallationDate: Installed on 2017-04-05 (393 days ago)
>   InstallationMedia: Ubuntu 16.10 "Yakkety Yak" - Release amd64
> (20161012.2)
>   MachineType: Dell Inc. XPS 13 9360
>   ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.15.0-20-generic
> root=/dev/mapper/ubuntu--vg-root ro quiet splash
> transparent_hugepage=madvise vt.handoff=1
>   SourcePackage: qemu
>   UpgradeStatus: Upgraded to bionic on 2018-04-30 (3 days ago)
>   dmi.bios.date: 02/26/2018
>   dmi.bios.vendor: Dell Inc.
>   dmi.bios.version: 2.6.2
>   dmi.board.name: 0PF86Y
>   dmi.board.vendor: Dell Inc.
>   dmi.board.version: A00
>   dmi.chassis.type: 9
>   dmi.chassis.vendor: Dell Inc.
>   dmi.modalias: dmi:bvnDellInc.:bvr2.6.2:bd02/26/2018:svnDellInc.:
> pnXPS139360:pvr:rvnDellInc.:rn0PF86Y:rvrA00:cvnDellInc.:ct9:cvr:
>   dmi.product.family: XPS
>   dmi.product.name: XPS 13 9360
>   dmi.sys.vendor: Dell Inc.
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/qemu/+bug/1769053/+subscriptions
>

-- 
You received this bug notification because you are a member of qemu-
devel-ml, which is subscribed to QEMU.
https://bugs.launchpad.net/bugs/1769053

Title:
  Cannot start a guest with more than 1TB of RAM

Status in QEMU:
  Incomplete
Status in qemu package in Ubuntu:
  Incomplete

Bug description:
  Attempting to start a KVM guest with more than 1TB of RAM fails.

  It looks like we might need some extra patches:
  https://lists.gnu.org/archive/html/qemu-discuss/2017-12/msg00005.html

  ProblemType: Bug
  DistroRelease: Ubuntu 18.04
  Package: qemu-system-x86 1:2.11+dfsg-1ubuntu7
  ProcVersionSignature: Ubuntu 4.15.0-20.21-generic 4.15.17
  Uname: Linux 4.15.0-20-generic x86_64
  ApportVersion: 2.20.9-0ubuntu7
  Architecture: amd64
  CurrentDesktop: Unity:Unity7:ubuntu
  Date: Fri May  4 16:21:14 2018
  InstallationDate: Installed on 2017-04-05 (393 days ago)
  InstallationMedia: Ubuntu 16.10 "Yakkety Yak" - Release amd64 (20161012.2)
  MachineType: Dell Inc. XPS 13 9360
  ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.15.0-20-generic root=/dev/mapper/ubuntu--vg-root ro quiet splash transparent_hugepage=madvise vt.handoff=1
  SourcePackage: qemu
  UpgradeStatus: Upgraded to bionic on 2018-04-30 (3 days ago)
  dmi.bios.date: 02/26/2018
  dmi.bios.vendor: Dell Inc.
  dmi.bios.version: 2.6.2
  dmi.board.name: 0PF86Y
  dmi.board.vendor: Dell Inc.
  dmi.board.version: A00
  dmi.chassis.type: 9
  dmi.chassis.vendor: Dell Inc.
  dmi.modalias: dmi:bvnDellInc.:bvr2.6.2:bd02/26/2018:svnDellInc.:pnXPS139360:pvr:rvnDellInc.:rn0PF86Y:rvrA00:cvnDellInc.:ct9:cvr:
  dmi.product.family: XPS
  dmi.product.name: XPS 13 9360
  dmi.sys.vendor: Dell Inc.

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