From owner-freebsd-current@FreeBSD.ORG Tue Jan 24 12:09:07 2012 Return-Path: Delivered-To: current@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 0F93A1065674; Tue, 24 Jan 2012 12:09:07 +0000 (UTC) (envelope-from avg@FreeBSD.org) Received: from citadel.icyb.net.ua (citadel.icyb.net.ua [212.40.38.140]) by mx1.freebsd.org (Postfix) with ESMTP id 2B54B8FC1D; Tue, 24 Jan 2012 12:09:05 +0000 (UTC) Received: from odyssey.starpoint.kiev.ua (alpha-e.starpoint.kiev.ua [212.40.38.101]) by citadel.icyb.net.ua (8.8.8p3/ICyb-2.3exp) with ESMTP id OAA20560; Tue, 24 Jan 2012 14:09:04 +0200 (EET) (envelope-from avg@FreeBSD.org) Message-ID: <4F1E9F5F.8080209@FreeBSD.org> Date: Tue, 24 Jan 2012 14:09:03 +0200 From: Andriy Gapon User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:9.0) Gecko/20120111 Thunderbird/9.0 MIME-Version: 1.0 To: Gleb Smirnoff References: <4F1ABFF3.9090305@FreeBSD.org> <20120122163539.GF16676@glebius.int.ru> <4F1D18A5.8010006@FreeBSD.org> <20120123130743.GI16676@glebius.int.ru> <4F1D6830.60602@FreeBSD.org> <20120123162410.GN16676@glebius.int.ru> <20120123162606.GO16676@FreeBSD.org> <4F1D8E2B.30800@FreeBSD.org> <20120123164659.GQ16676@glebius.int.ru> <4F1D9128.3030501@FreeBSD.org> <20120124115424.GX16676@glebius.int.ru> In-Reply-To: <20120124115424.GX16676@glebius.int.ru> X-Enigmail-Version: undefined Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: current@FreeBSD.org Subject: Re: new panic in cpu_reset() with WITNESS X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 24 Jan 2012 12:09:07 -0000 on 24/01/2012 13:54 Gleb Smirnoff said the following: > On Mon, Jan 23, 2012 at 06:56:08PM +0200, Andriy Gapon wrote: > A> on 23/01/2012 18:46 Gleb Smirnoff said the following: > A> > On Mon, Jan 23, 2012 at 06:43:23PM +0200, Andriy Gapon wrote: > A> > A> > db> bt > A> > A> > Tracing pid 1 tid 100001 td 0xfffffe0001d5e000 > A> > A> > kdb_enter() at kdb_enter+0x3b > A> > A> > panic() at panic+0x1c7 > A> > A> > _mtx_lock_spin_flags() at _mtx_lock_spin_flags+0x10f > A> > A> > cnputs() at cnputs+0x7a > A> > A> > vprintf() at vprintf+0xcb > A> > A> > printf() at printf+0x67 > A> > A> > db_putc() at db_putc+0x81 > A> > A> > A> > A> Ah, db_putc does something different from what I expected. > A> > A> Can you hack it to never use printf? > A> > > A> > Just cut printfs from db_putc()? > A> > A> Make the following condition be always false: > A> > A> if (!kdb_active || ddb_use_printf) { > A> > A> E.g.: > A> > A> if (0) { > > With this change + s/printf/db_printf/ in subr_witness.c I've > got the following during reboot: > > Rebooting... > lllock order reversal: > 1st 0xffffffff80937140 smp rendezvous (smp rendezvous) @ /usr/src/head/sys/kern/kern_shutdown.c:542 > 2nd 0xffffffff80b13280 syscons video lock (syscons video lock) @ /usr/src/head/sys/dev/syscons/syscons.c:1921 > panic: mtx_lock_spin: recursed on non-recursive mutex cnputs_mtx @ /usr/src/head/sys/kern/kern_cons.c:500 Can you disable video console? -- Andriy Gapon