[PATCH v3 0/3] Disable Deprecated Features by Default on s390 CPU Models
Changelog
v3
- added qemu caps check to avoid breaking s390 guests trying to
default deprecated_features='off' on QEMU versions that
do not support reporting these features
v2
- changed behavior from disabling features on the host model to
instead flagging the guest CPU to disable deprecated features
- removed disabling deprecated features on host model in
virQEMUCapsInitCPUModelS390
- added flagging deprecated_feats in qemuProcessUpdateGuestCPU
- added tests for deprecated_features='on'
- split virQEMUCapsUpdateCPUDeprecatedFeatures update and
qemuProcessUpdateGuestCPU changes
The intention of reporting deprecated features and modifying the guest
CPU model was to alleviate the user from the burden of preparing a guest
with the necessary amendments to assure migration to newer hardware.
While that goal was met by way of the "deprecated_features='on|off'"
attribute, it still adds an extra step that the user must be aware to
prepare a guest for migration and the errors that stem from an
unsuccessful migration (due to feature incompatibility) is not always
clear how to resolve.
These patches make s390 CPU host models migration ready from the get-go
by disabling deprecated features by default. They may still be disabled
for other model types via the respective attribute, or reenabled if
desired.
Collin Walling (3):
qemu: caps: add virCPUFeaturePolicy param to
virQEMUCapsUpdateCPUDeprecatedFeatures
qemu: process: refactor deprecated features code
qemu: process: disable deprecated features for s390 models by default
src/qemu/qemu_capabilities.c | 6 ++--
src/qemu/qemu_capabilities.h | 3 +-
src/qemu/qemu_driver.c | 3 +-
src/qemu/qemu_process.c | 32 ++++++++++++++-----
...l-deprecated-features-on.s390x-latest.args | 32 +++++++++++++++++++
...el-deprecated-features-on.s390x-latest.xml | 25 +++++++++++++++
.../cpu-model-deprecated-features-on.xml | 15 +++++++++
...default-video-type-s390x.s390x-latest.args | 2 +-
...vfio-zpci-ccw-memballoon.s390x-latest.args | 2 +-
.../launch-security-s390-pv.s390x-latest.args | 2 +-
...t-cpu-kvm-ccw-virtio-4.2.s390x-latest.args | 2 +-
.../s390-defaultconsole.s390x-latest.args | 2 +-
.../s390-panic.s390x-latest.args | 2 +-
tests/qemuxmlconftest.c | 1 +
14 files changed, 110 insertions(+), 19 deletions(-)
create mode 100644
tests/qemuxmlconfdata/cpu-model-deprecated-features-on.s390x-latest.args
create mode 100644
tests/qemuxmlconfdata/cpu-model-deprecated-features-on.s390x-latest.xml
create mode 100644 tests/qemuxmlconfdata/cpu-model-deprecated-features-on.xml
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2.47.1