tree 5b0c1010a027aa79139a0dd2bd205a7984effa57
parent 0fa9131a44943cc14c931a23eee040da4cc0c454
author Kevin Wolf <kwolf@redhat.com> 1314886570 +0200
committer Kevin Wolf <kwolf@redhat.com> 1315301031 +0200

async: Allow nested qemu_bh_poll calls

qemu may segfault when a BH handler first deletes a BH and then (possibly
indirectly) calls a nested qemu_bh_poll(). This is because the inner instance
frees the BH and deletes it from the list that the outer one processes.

This patch deletes BHs only in the outermost qemu_bh_poll instance.

Commit 7887f620 already tried to achieve the same, but it assumed that the BH
handler would only delete its own BH. With a nested qemu_bh_poll(), this isn't
guaranteed, so that commit wasn't enough. Hope this one fixes it for real.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>