Re: [PATCH V2 00/11] allow cpr-reboot for vfio

[Steven Sistare]

On 1/12/2024 4:38 PM, Alex Williamson wrote:
> On Fri, 12 Jan 2024 07:04:59 -0800
> Steve Sistare <steven.sistare@oracle.com> wrote:
> 
>> Allow cpr-reboot for vfio if the guest is in the suspended runstate.  The
>> guest drivers' suspend methods flush outstanding requests and re-initialize
>> the devices, and thus there is no device state to save and restore.  The
>> user is responsible for suspending the guest before initiating cpr, such as
>> by issuing guest-suspend-ram to the qemu guest agent.
>>
>> Most of the patches in this series enhance migration notifiers so they can
>> return an error status and message.  The last two patches register a notifier
>> for vfio that returns an error if the guest is not suspended.
> 
> Hi Steve,
> 
> This appears to only support legacy container mode and not cdev/iommufd
> mode.  Shouldn't this support both?  Thanks,

My bad, thanks! I'll move cpr_reboot_notifier to the base container, and also 
call
cpr register/unregister from iommufd_cdev_attach/iommufd_cdev_detach.

- Steve

>> Steve Sistare (11):
>>   notify: pass error to notifier with return
>>   migration: remove error from notifier data
>>   migration: convert to NotifierWithReturn
>>   migration: remove migration_in_postcopy parameter
>>   migration: MigrationEvent for notifiers
>>   migration: MigrationNotifyFunc
>>   migration: per-mode notifiers
>>   migration: refactor migrate_fd_connect failures
>>   migration: notifier error checking
>>   vfio: register container for cpr
>>   vfio: allow cpr-reboot migration if suspended
>>
>>  hw/net/virtio-net.c            |  14 ++---
>>  hw/vfio/common.c               |   2 +-
>>  hw/vfio/container.c            |  11 +++-
>>  hw/vfio/cpr.c                  |  39 ++++++++++++++
>>  hw/vfio/meson.build            |   1 +
>>  hw/vfio/migration.c            |  13 +++--
>>  hw/virtio/vhost-user.c         |  10 ++--
>>  hw/virtio/virtio-balloon.c     |   3 +-
>>  include/hw/vfio/vfio-common.h  |   6 ++-
>>  include/hw/virtio/virtio-net.h |   2 +-
>>  include/migration/misc.h       |  21 +++++---
>>  include/qemu/notify.h          |   7 ++-
>>  migration/migration.c          | 117 
>> +++++++++++++++++++++++++++--------------
>>  migration/postcopy-ram.c       |   3 +-
>>  migration/postcopy-ram.h       |   1 -
>>  migration/ram.c                |  12 ++---
>>  net/vhost-vdpa.c               |  15 +++---
>>  ui/spice-core.c                |  19 +++----
>>  util/notify.c                  |   5 +-
>>  19 files changed, 206 insertions(+), 95 deletions(-)
>>  create mode 100644 hw/vfio/cpr.c
>>
>