LOR route vr0
rwatson at FreeBSD.org
Sun Aug 28 04:20:17 GMT 2005
On Sat, 27 Aug 2005, M. Warner Losh wrote:
> : Correct. 'tcp' reflects the global TCP state tables (pcbinfo) locks, and
> : 'tcpinp' is for individual PCBs. If you acquire first a tcpinp and then
> : tcp, the above settings should cause WITNESS to generate a lock order
> : warning. Likewise, both tcp and tcpinp preceed so_snd, so if you acquire
> : a protocol lock after a socket lock, it will get unhappy. WITNESS handles
> : transitive relationships, so it gets connected up to the rest of the lock
> : graph, explicit and implicit, so indirect violations of orders are fully
> : handled.
> OK. I've been seeing similar LORs in ed, sn, iwi (ed is my locked
> version of ed, not in tree GIANT locked ed).
> I've made the following changes, and the LORs go away (except for one,
> which was unrelated). I further don't get the first place where they
> locks happen that caused the original LORs, so I'm mightly confused.
Hmm. I've seen another identical report recently -- that when a lock
order is put into WITNESS, reversals against it are not reported. I
wonder if we've got a witness bug on our hands?
Robert N M Watson
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