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Who When What Removed Added
Jiri Denemark 2017-11-01 21:19:51 UTC Status NEW ASSIGNED
Assignee libvirt-maint jdenemar
Jiri Denemark 2017-11-02 16:37:58 UTC Status ASSIGNED POST
Doc Text Cause: After upgrading libvirt to RHEL-7.4 while some QEMU/KVM domains with "host-model" CPU were running, libvirt could mark the domains as using a CPU feature which QEMU does not know.

Consequence: This doesn't affect the running domains until they are saved, migrated, or their snapshot is made. Migrating such domain or restoring it from a saved state fails with a complain about unknown "cmt" feature.

Fix: With this update, libvirt no longer adds unknown CPU features to guest CPU configuration. Moreover, if any domain which was running before the upgrade to RHEL-7.4 is still running, libvirt will automatically fix its configuration. And if such domain was saved, libvirt will drop the unknown CPU feature when it is asked to restore the domain.

Result: Domains running before the upgrade to RHEL-7.4 can be migrated or restored if they were saved in the meantime.
Doc Type If docs needed, set a value Bug Fix
Xuesong Zhang 2017-11-03 10:26:53 UTC QA Contact virt-bugs zpeng
Jiri Denemark 2017-11-06 15:00:55 UTC Status POST MODIFIED
Fixed In Version libvirt-3.2.0-14.el7_4.4
errata-xmlrpc 2017-11-06 15:09:38 UTC Status MODIFIED ON_QA
Thomas Oulevey 2017-11-08 10:46:26 UTC CC thomas.oulevey
Thomas Oulevey 2017-11-08 10:46:47 UTC CC thomas.oulevey
Luyao Huang 2017-11-13 08:47:53 UTC CC lhuang
Flags needinfo?(jdenemar)
Jiri Denemark 2017-11-13 17:35:26 UTC Flags needinfo?(jdenemar) needinfo?(lhuang)
Luyao Huang 2017-11-14 02:04:00 UTC Flags needinfo?(lhuang)
Jason 2017-11-14 14:34:24 UTC CC jbryant
Roman Hodain 2017-11-14 14:51:43 UTC Flags needinfo?(jdenemar)
Jiri Denemark 2017-11-15 14:40:52 UTC Flags needinfo?(jdenemar)
zhe peng 2017-11-16 08:09:14 UTC Status ON_QA VERIFIED
Jiri Herrmann 2017-11-16 16:54:23 UTC CC jherrman
Doc Text Cause: After upgrading libvirt to RHEL-7.4 while some QEMU/KVM domains with "host-model" CPU were running, libvirt could mark the domains as using a CPU feature which QEMU does not know.

Consequence: This doesn't affect the running domains until they are saved, migrated, or their snapshot is made. Migrating such domain or restoring it from a saved state fails with a complain about unknown "cmt" feature.

Fix: With this update, libvirt no longer adds unknown CPU features to guest CPU configuration. Moreover, if any domain which was running before the upgrade to RHEL-7.4 is still running, libvirt will automatically fix its configuration. And if such domain was saved, libvirt will drop the unknown CPU feature when it is asked to restore the domain.

Result: Domains running before the upgrade to RHEL-7.4 can be migrated or restored if they were saved in the meantime.
Previously, the libvirt service in some cases added the "cmt" CPU feature incompatible with the QEMU emulator to KVM guest virtual machines with CPU set to "host-model". As a consequence, migrating or restoring these guests failed. With this update, libvirt no longer adds "cmt" to domain features and automatically removes "cmt" from guest configuration if present. As a result, the affected guests can be migrated and restored correctly.
errata-xmlrpc 2017-11-30 07:50:08 UTC Status VERIFIED RELEASE_PENDING
errata-xmlrpc 2017-11-30 16:06:34 UTC Status RELEASE_PENDING CLOSED
Resolution --- ERRATA
Last Closed 2017-11-30 11:06:34 UTC

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