K 10
svn:author
V 3
mjg
K 8
svn:date
V 27
2020-02-16T03:14:55.426892Z
K 7
svn:log
V 540
refcount: add missing release fence to refcount_release_if_gt

The CPU succeeding in releasing the not last reference can still have pending
stores to the object protected by the affected counter. This opens a time
window where another CPU can release the last reference and free the object,
resulting in use-after-free. On top of that this prevents the compiler from
generating more accesses to the object regardless of how atomic_fcmpset_rel_int
is implemented (of course as long as it provides the release semantic).

Reviewed by:	markj

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