diff options
Diffstat (limited to 'docs/devel')
| -rw-r--r-- | docs/devel/migration/main.rst | 6 | ||||
| -rw-r--r-- | docs/devel/replay.rst | 3 |
2 files changed, 9 insertions, 0 deletions
diff --git a/docs/devel/migration/main.rst b/docs/devel/migration/main.rst index 784c899dca..c2857fc244 100644 --- a/docs/devel/migration/main.rst +++ b/docs/devel/migration/main.rst @@ -465,6 +465,12 @@ Examples of such API functions are: - portio_list_set_address() - portio_list_set_enabled() +Since the order of device save/restore is not defined, you must +avoid accessing or changing any other device's state in one of these +callbacks. (For instance, don't do anything that calls ``update_irq()`` +in a ``post_load`` hook.) Otherwise, restore will not be deterministic, +and this will break execution record/replay. + Iterative device migration -------------------------- diff --git a/docs/devel/replay.rst b/docs/devel/replay.rst index effd856f0c..40f58d9d4f 100644 --- a/docs/devel/replay.rst +++ b/docs/devel/replay.rst @@ -202,6 +202,9 @@ into the log. Saving/restoring the VM state ----------------------------- +Record/replay relies on VM state save and restore being complete and +deterministic. + All fields in the device state structure (including virtual timers) should be restored by loadvm to the same values they had before savevm. |