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Two questions about VFIO device live migration
Description of problem:
For my own pcie device, i implement system memory && device memory dirty bitmap track and works well
use pre-copy mode live migration by the way.
first question:
- for system memory dirty bitmap sync, notice that last sync will come early than i expected
read qemu code and found qemu will call every savevm_state.handlers->save_live_complete_precopy callback
in "qemu_savevm_state_complete_precopy_iterable", and "vfio" handler will always behind "ram".
so here is question, my own vfio device will only be halted after "vfio" handler enter
save_live_complete_precopy, and last system memory dirty bitmap sync will come with "ram"'s
save_live_complete_precopy, there will be some system dirty between this period, should we add one more
system dirty bitmap sync after "vfio"'s save_live_complete_precopy
second question:
- notice that qemu will clean up migration and call every savevm_state.handlers->save_cleanup call back, and
in this function, qemu will only call vfio listener's log_global_stop call back when vm_is_running
but for my vfio device, state will be paused(postmigrate) when enter here, so there is no chance for qemu
to relese some resource create by my device kernel mode driver, where should i put the logic about "stop
migration resource" anyway
Thanks ^_^
Steps to reproduce:
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Additional information:
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