From owner-freebsd-doc@FreeBSD.ORG Thu Dec 6 11:50:01 2012 Return-Path: Delivered-To: freebsd-doc@smarthost.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 2EC0AAEF for ; Thu, 6 Dec 2012 11:50:01 +0000 (UTC) (envelope-from gnats@FreeBSD.org) Received: from freefall.freebsd.org (freefall.freebsd.org [IPv6:2001:1900:2254:206c::16:87]) by mx1.freebsd.org (Postfix) with ESMTP id DBCA48FC13 for ; Thu, 6 Dec 2012 11:50:00 +0000 (UTC) Received: from freefall.freebsd.org (localhost [127.0.0.1]) by freefall.freebsd.org (8.14.5/8.14.5) with ESMTP id qB6Bo0kL039838 for ; Thu, 6 Dec 2012 11:50:00 GMT (envelope-from gnats@freefall.freebsd.org) Received: (from gnats@localhost) by freefall.freebsd.org (8.14.5/8.14.5/Submit) id qB6Bo0bj039837; Thu, 6 Dec 2012 11:50:00 GMT (envelope-from gnats) Resent-Date: Thu, 6 Dec 2012 11:50:00 GMT Resent-Message-Id: <201212061150.qB6Bo0bj039837@freefall.freebsd.org> Resent-From: FreeBSD-gnats-submit@FreeBSD.org (GNATS Filer) Resent-To: freebsd-doc@FreeBSD.org Resent-Reply-To: FreeBSD-gnats-submit@FreeBSD.org, Bas Smeelen Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id D8F5AAE2 for ; Thu, 6 Dec 2012 11:49:11 +0000 (UTC) (envelope-from nobody@FreeBSD.org) Received: from red.freebsd.org (red.freebsd.org [IPv6:2001:4f8:fff6::22]) by mx1.freebsd.org (Postfix) with ESMTP id B59878FC12 for ; Thu, 6 Dec 2012 11:49:11 +0000 (UTC) Received: from red.freebsd.org (localhost [127.0.0.1]) by red.freebsd.org (8.14.5/8.14.5) with ESMTP id qB6BnAdx015251 for ; Thu, 6 Dec 2012 11:49:10 GMT (envelope-from nobody@red.freebsd.org) Received: (from nobody@localhost) by red.freebsd.org (8.14.5/8.14.5/Submit) id qB6BnAD3015250; Thu, 6 Dec 2012 11:49:10 GMT (envelope-from nobody) Message-Id: <201212061149.qB6BnAD3015250@red.freebsd.org> Date: Thu, 6 Dec 2012 11:49:10 GMT From: Bas Smeelen To: freebsd-gnats-submit@FreeBSD.org X-Send-Pr-Version: www-3.1 Subject: docs/174226: [patch] faq: lock-order-reversal X-BeenThere: freebsd-doc@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Documentation project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 06 Dec 2012 11:50:01 -0000 >Number: 174226 >Category: docs >Synopsis: [patch] faq: lock-order-reversal >Confidential: no >Severity: non-critical >Priority: low >Responsible: freebsd-doc >State: open >Quarter: >Keywords: >Date-Required: >Class: update >Submitter-Id: current-users >Arrival-Date: Thu Dec 06 11:50:00 UTC 2012 >Closed-Date: >Last-Modified: >Originator: Bas Smeelen >Release: 9.1 >Organization: >Environment: FreeBSD cfd 9.1-RELEASE FreeBSD 9.1-RELEASE #1 r243880: Wed Dec 5 08:15:54 CET 2012 root@cfd:/usr/obj/usr/src/sys/GENERIC i386 >Description: >How-To-Repeat: >Fix: Index: book.xml =================================================================== --- book.xml (revision 40280) +++ book.xml (working copy) @@ -3488,9 +3488,20 @@ - An answer for this question can be found in the &os; - Glossary, see LOR. + The &os; kernel uses a number of resource locks to + arbitrate contention for those resources. A run-time + lock diagnostic system found in &os.current; kernels + (but removed for releases), called &man.witness.4;, + detects the potential for deadlocks due to locking errors. + (&man.witness.4; is actually slightly conservative, so + it is possible to get false positives.) A true positive + report indicates that if you were unlucky, a deadlock would + have happened here. + + True positive LORs tend to get fixed quickly, so + check &a.current.url; and the + LORs Seen + page before posting to the mailing lists. >Release-Note: >Audit-Trail: >Unformatted: