On 10/27/23 20:21, Sean Christopherson wrote:
Add an assertion that there are no in-progress MMU invalidations when a
VM is being destroyed, with the exception of the scenario where KVM
unregisters its MMU notifier between an .invalidate_range_start() call
and the corresponding .invalidate_range_end(). KVM can't detect unpaired
calls from the mmu_notifier due to the above exception waiver, but the
assertion can detect KVM bugs, e.g. such as the bug that *almost*
escaped initial guest_memfd development.
Link: https://lore.kernel.org/all/e397d30c-c6af-e68f-d18e-b4e3739c5389@xxxxxxxxxxxxxxx
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Reviewed-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Paolo