From owner-freebsd-net@FreeBSD.ORG Tue Nov 24 02:30:06 2009 Return-Path: Delivered-To: freebsd-net@hub.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id A6860106566B for ; Tue, 24 Nov 2009 02:30:06 +0000 (UTC) (envelope-from gnats@FreeBSD.org) Received: from freefall.freebsd.org (freefall.freebsd.org [IPv6:2001:4f8:fff6::28]) by mx1.freebsd.org (Postfix) with ESMTP id 96AA38FC1C for ; Tue, 24 Nov 2009 02:30:06 +0000 (UTC) Received: from freefall.freebsd.org (localhost [127.0.0.1]) by freefall.freebsd.org (8.14.3/8.14.3) with ESMTP id nAO2U6Iv004172 for ; Tue, 24 Nov 2009 02:30:06 GMT (envelope-from gnats@freefall.freebsd.org) Received: (from gnats@localhost) by freefall.freebsd.org (8.14.3/8.14.3/Submit) id nAO2U6Ak004167; Tue, 24 Nov 2009 02:30:06 GMT (envelope-from gnats) Date: Tue, 24 Nov 2009 02:30:06 GMT Message-Id: <200911240230.nAO2U6Ak004167@freefall.freebsd.org> To: freebsd-net@FreeBSD.org From: Benjamin Kaduk Cc: Subject: Re: kern/140036: [iwn] [lor] lock order reversal with iwn0_com_lock and iwn0 softc lock X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: Benjamin Kaduk List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 24 Nov 2009 02:30:06 -0000 The following reply was made to PR kern/140036; it has been noted by GNATS. From: Benjamin Kaduk To: Bernhard Schmidt Cc: bug-followup@freebsd.org Subject: Re: kern/140036: [iwn] [lor] lock order reversal with iwn0_com_lock and iwn0 softc lock Date: Mon, 23 Nov 2009 21:27:15 -0500 (EST) On Mon, 23 Nov 2009, Benjamin Kaduk wrote: > On Sun, 22 Nov 2009, Bernhard Schmidt wrote: >> >> Can you verify that the LOR is gone with the latest checkout of my >> repository? >> Compile instructions: >> http://forums.freebsd.org/showpost.php?p=47627&postcount=16 > > I upgraded to today's current (which picked up a number of probably-unrelated > changes), and then installed the driver from > your tree on top of it. > No LOR on boot, and I'll let you know if I see any lockups. I got a "lockup" (no idea what actually was happening) while in X tonight; nothing useful is in the logs. I'm not even sure if I can blame iwn for it ... I did get a LOR after turning on the hardware wireless switch, though: iwn0: RF switch: radio enabled wlan0: link state changed to UP lock order reversal: 1st 0xffffff800033d018 iwn0_com_lock (iwn0_com_lock) @ /usr/devel/iwn/freebsd/sys/modules/iwn/../../dev/iwn/if_iwn.c:3280 2nd 0xffffff8000309010 iwn0 (network driver) @ /usr/devel/iwn/freebsd/sys/modules/iwn/../../dev/iwn/if_iwn.c:3289 KDB: stack backtrace: db_trace_self_wrapper() at db_trace_self_wrapper+0x2a _witness_debugger() at _witness_debugger+0x2e witness_checkorder() at witness_checkorder+0x81e _mtx_lock_flags() at _mtx_lock_flags+0x78 iwn_start() at iwn_start+0x35 if_transmit() at if_transmit+0xd6 ieee80211_start() at ieee80211_start+0x3f4 scan_task() at scan_task+0x4c7 taskqueue_run() at taskqueue_run+0x91 taskqueue_thread_loop() at taskqueue_thread_loop+0x3f fork_exit() at fork_exit+0x12a fork_trampoline() at fork_trampoline+0xe --- trap 0, rip = 0, rsp = 0xffffff80001ffd30, rbp = 0 --- I don't think I'll have time to look at it particularly soon, though. -Ben Kaduk