iothread: Make iothread_stop() idempotent
Currently, iothread_stop_all() makes all iothread objects unsafe
to be destroyed, because qemu_thread_join() ends up being called
twice.
To fix this, make iothread_stop() idempotent by checking
thread->stopped.
Fixes the following crash:
qemu-system-x86_64 -object iothread,id=iothread0 -monitor stdio -display none
QEMU 2.10.50 monitor - type 'help' for more information
(qemu) quit
qemu: qemu_thread_join: No such process
Aborted (core dumped)
Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <
20170926130028.12471-1-ehabkost@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>