RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.
Bug 1687275 - Guest (KVM, with 5-level paging enabled) boot up with the wrong address width on the host (5-level paging & EPT5 enabled)
Summary: Guest (KVM, with 5-level paging enabled) boot up with the wrong address width...
Keywords:
Status: CLOSED WONTFIX
Alias: None
Product: Red Hat Enterprise Linux 8
Classification: Red Hat
Component: qemu-kvm
Version: 8.0
Hardware: x86_64
OS: Linux
high
high
Target Milestone: rc
: 8.1
Assignee: Eduardo Habkost
QA Contact: Yumei Huang
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2019-03-11 07:32 UTC by belinda
Modified: 2021-03-31 08:59 UTC (History)
14 users (show)

Fixed In Version:
Doc Type: If docs needed, set a value
Doc Text:
Clone Of:
Environment:
Last Closed: 2019-04-05 00:07:52 UTC
Type: Bug
Target Upstream Version:
Embargoed:

Attachments (Terms of Use)

Description belinda 2019-03-11 07:32:19 UTC 
Description of problem:
Guest (KVM, with 5-level paging enabled) boot up with the wrong address width on the host (5-level paging & EPT5 enabled)

Version-Release number of selected component (if applicable):
RHEL-8.0-Snapshot-6

How reproducible:

[Test environment]
Hardware : ICX platform(emulated by Simics) or newer
Host OS : RHEL-8.0-Snapshot-6
Host kernel: 4.18.0-67.el8.x86_64
Host QEMU: QEMU emulator version 2.12.0 (qemu-kvm-2.12.0-61.module+el8+2786+5afd5ae3)
Guest OS : RHEL-8.0-Snapshot-6
Guest kernel : 4.18.0-67.el8.x86_64


Steps to Reproduce:
Try to Check Guest (KVM, with 5-level paging enabled) can boot up with the correct address bit width on the host (5-level paging & EPT5 enabled)
1.prepare ICX server emulated using simics.
2.To execute the following qemu command for boot up Guest (with 5-level paging enabled) on ICX server (host, 5-level paging & EPT5 enabled): 
#qemu-img create -b /opt/zxf/rhel_8.0snap6_EFI5level.img -f qcow2 /opt/rhel8.0.qcow
#qemu-system-x86_64 -enable-kvm -m 4096 -smp 4  -cpu qemu64,+la57,phys-bits=52 -drive file=/opt/rhel8.0.qcow -vnc :8 -bios /usr/local/share/qemu/OVMF.fd
qemu-system-x86_64: warning: Host physical bits (52) does not match phys-bits property (48)
3. Try to check the address of guest via executing the following qemu command on guest:  
#cat /proc/cpuinfo |grep address|uniq


Actual results:
On step3:
 “#cat /proc/cpuinfo |grep address|uniq” shown:
address sizes   : 48 bits physical, 57 bits virtual


Expected results:
on step3:
“#cat /proc/cpuinfo |grep address|uniq” should show :
address sizes   : 52 bits physical, 57 bits virtual


Additional info:none
Comment 1 Eduardo Habkost 2019-03-30 21:42:15 UTC 
We have host-phys-bits=on by default, and it overrides the "phys-bits" option.  Is the problem reproducible using "cpu qemu64,+la57,phys-bits=52,host-phys-bits=off"?
Comment 4 Eduardo Habkost 2019-04-02 00:32:36 UTC 
Re-setting needinfo flag from comment #1.
Comment 5 belinda 2019-04-04 01:11:19 UTC 
We verified this bug not reproduced when we use "cpu qemu64,+la57,phys-bits=52,host-phys-bits=off" on RHEL8.0 RC2.
and if we use "cpu qemu64,+la57,phys-bits=52", bug still reproduced on RHEL8.0 RC2.
Comment 6 Eduardo Habkost 2019-04-05 00:07:52 UTC 
(In reply to belinda from comment #5)
> We verified this bug not reproduced when we use "cpu
> qemu64,+la57,phys-bits=52,host-phys-bits=off" on RHEL8.0 RC2.
> and if we use "cpu qemu64,+la57,phys-bits=52", bug still reproduced on
> RHEL8.0 RC2.

Thanks for the information.  As we don't support customers running QEMU directly, we will address this issue upstream but it won't be a priority for RHEL.  Test engineers will need to take host-phys-bits into account and use host-phys-bits=off when testing the phys-bits feature.
Note You need to log in before you can comment on or make changes to this bug.