From: ChristianEhrhardt <1769053@bugs.launchpad.net>
To: qemu-devel@nongnu.org
Subject: [Qemu-devel] [Bug 1769053] Re: Cannot start a guest with more than 1TB of RAM
Date: Mon, 07 May 2018 10:33:34 -0000 [thread overview]
Message-ID: <152568921469.6485.15990399219355923244.malone@chaenomeles.canonical.com> (raw)
In-Reply-To: 152541524728.557.4600864098110042577.malonedeb@gac.canonical.com
> Interesting; I thought this was supposed to work.
Exactly that was my thought when triaging it initially
Furthermore I assume people working la57 (https://lwn.net/Articles/730925/) and such ran tests on much bigger sizes.
> Ah right Dan, if you're seeing the 40 bits physical in the guest you
definitely need to try the flags I suggest in comment 6; host-phys-
bits=true should work for you.
I tested Bionic to be at least on libvirt 4.0 / qemu 2.11.1 when we want
to check things under the "supposed to work now" flag.
Defaults:
Host: address sizes : 46 bits physical, 48 bits virtual
Guest: address sizes : 40 bits physical, 48 bits virtual
I ensured that with option -cpu host,host-phys-bits=true set I successfully get what my host can provide in the guest:
Guest: address sizes : 46 bits physical, 48 bits virtual
Starting a guest with that >1TB (that would be mostly on swap if needed) works just fine as expected. Here ~1063 GB from /proc/meminfo
MemTotal: 1114676492 kB
I also checked a more compatible approach like -cpu qemu64,phys-bits=42
and that works as well.
IMHO - if anything - one could argue that libvirt/qemu could be smarter
about e.g. auto adding those arguments (or print a warning) when
crossing a certain memory size.
So for now I'd stick to the "actually works" summary and keep the status
to incomplete.
--
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.
To manage notifications about this bug go to:
https://bugs.launchpad.net/qemu/+bug/1769053/+subscriptions
next prev parent reply other threads:[~2018-05-07 10:41 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <152541524728.557.4600864098110042577.malonedeb@gac.canonical.com>
2018-05-04 6:46 ` [Qemu-devel] [Bug 1769053] Re: Cannot start a guest with more than 1TB of RAM Daniel Axtens
2018-05-04 7:44 ` ChristianEhrhardt
2018-05-04 8:04 ` Daniel Axtens
2018-05-04 8:12 ` ChristianEhrhardt
2018-05-04 16:10 ` Dr. David Alan Gilbert
2018-05-04 16:14 ` Dan Streetman
2018-05-04 16:15 ` Dan Streetman
2018-05-04 16:19 ` Dan Streetman
2018-05-04 16:33 ` Dr. David Alan Gilbert
2018-05-07 10:33 ` ChristianEhrhardt [this message]
2018-05-08 8:37 ` Dr. David Alan Gilbert
2018-05-08 9:57 ` ChristianEhrhardt
2018-05-08 10:26 ` Dr. David Alan Gilbert
2018-05-08 10:48 ` Daniel Berrange
2018-05-08 11:23 ` Dr. David Alan Gilbert
2018-05-08 13:22 ` Gerd Hoffmann
2018-05-08 14:00 ` Dr. David Alan Gilbert
2018-05-15 1:16 ` David Coronel
2018-05-15 7:17 ` Christian Ehrhardt
2018-05-15 7:19 ` Christian Ehrhardt
2018-05-15 7:45 ` Christian Ehrhardt
2018-06-11 9:30 ` Christian Ehrhardt
2018-06-12 7:02 ` [Qemu-devel] [Bug 1769053] Re: Ability to control phys-bits through libvirt Launchpad Bug Tracker
2018-06-12 7:04 ` Christian Ehrhardt
2018-06-12 7:18 ` Launchpad Bug Tracker
2018-06-12 7:18 ` Christian Ehrhardt
2018-06-12 7:46 ` Launchpad Bug Tracker
2018-06-12 8:27 ` Christian Ehrhardt
2018-06-12 11:14 ` Launchpad Bug Tracker
2019-08-28 2:55 ` [Bug 1769053] sirswa
2019-08-28 14:16 ` ehabkost
2020-10-29 15:30 ` raistlin
2023-04-19 5:43 ` [Bug 1769053] Re: Ability to control phys-bits through libvirt Christian Ehrhardt
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=152568921469.6485.15990399219355923244.malone@chaenomeles.canonical.com \
--to=1769053@bugs.launchpad.net \
--cc=qemu-devel@nongnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).