> Hmm, looks like uao_free() drops the object lock before calling
> dropswap().  But the comment on dropswap() says it should be called with
> the object locked.

the comment is on uao_dropswap_range, not uao_dropswap_range1.
iirc, the object is dying here and no one should really care about the lock
at this point.

> So I'm guessing this should do the trick.  yamt?

i prefer to move the unlock immediately after uao_dropswap_range1.
otherwise it's fine.  please commit.

YAMAMOTO Takashi