Date: Mon, 31 Jul 2006 15:46:02 -0500 From: "Christian S.J. Peron" <csjp@FreeBSD.org> To: Robert Huff <roberthuff@rcn.com> Cc: freebsd-current@freebsd.org Subject: Re: LOR when booting CURRENT (ip_divert.c, PFil hook read/write mutex) [#181] Message-ID: <44CE6C0A.50009@FreeBSD.org> In-Reply-To: <17610.836.663396.331448@jerusalem.litteratus.org> References: <20060726063636.GA58151@freefall.freebsd.org> <17610.836.663396.331448@jerusalem.litteratus.org>
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Robert Huff wrote: > Yar Tikhiy writes: > > >> FWIW, the LOR still is there. I was seeing it yesterday while >> fiddling with the ipfw and natd rc.d scripts. >> >> lock order reversal: >> 1st 0xc1a36090 inp (divinp) @ /usr/src/sys/modules/ipdivert/../../netinet/ip_divert.c:350 >> 2nd 0xc0a51918 PFil hook read/write mutex (PFil hook read/write mutex) @ /usr/src/sys/net/pfil.c:73 >> > > For the record, I'm (still) getting this also. > > > Robert Huff > _______________________________________________ > freebsd-current@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-current > To unsubscribe, send any mail to "freebsd-current-unsubscribe@freebsd.org" > > > This appears to be similar to the LOR associated with IPFW and ucred based rules, I think. Although this is a lock order reversal and it probably isn't a false positive, it should be reasonably harmless, because the pfil hook lock is a reader lock, thus different threads can acquire it (at this point) con-currently, presumably preventing a dead lock from actually occurring here. iirc witness it not aware of the reader/writer semantics, so it makes sense that it will be dropping a warning here. But I can look at this in further detail when I get a bit of time. -- Christian S.J. Peron csjp@FreeBSD.ORG FreeBSD Committer FreeBSD Security Team
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