From owner-freebsd-current@FreeBSD.ORG Tue Jul 31 17:17:41 2007 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 0624C16A418 for ; Tue, 31 Jul 2007 17:17:41 +0000 (UTC) (envelope-from marck@rinet.ru) Received: from woozle.rinet.ru (woozle.rinet.ru [195.54.192.68]) by mx1.freebsd.org (Postfix) with ESMTP id 742AD13C4B4 for ; Tue, 31 Jul 2007 17:17:40 +0000 (UTC) (envelope-from marck@rinet.ru) Received: from localhost (localhost [127.0.0.1]) by woozle.rinet.ru (8.14.1/8.14.1) with ESMTP id l6VHHcXs022504; Tue, 31 Jul 2007 21:17:38 +0400 (MSD) (envelope-from marck@rinet.ru) Date: Tue, 31 Jul 2007 21:17:38 +0400 (MSD) From: Dmitry Morozovsky To: Maksim Yevmenkin In-Reply-To: Message-ID: <20070731211230.B15561@woozle.rinet.ru> References: <20070727141421.H42349@woozle.rinet.ru> <20070728173355.O42349@woozle.rinet.ru> <20070731123820.T29245@woozle.rinet.ru> X-NCC-RegID: ru.rinet X-OpenPGP-Key-ID: 6B691B03 MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-3.0 (woozle.rinet.ru [0.0.0.0]); Tue, 31 Jul 2007 21:17:38 +0400 (MSD) Cc: current@freebsd.org Subject: Re: possible showstopper: kbdmux hangs -current 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, 31 Jul 2007 17:17:41 -0000 On Tue, 31 Jul 2007, Maksim Yevmenkin wrote: MY> > MY> > MY> > on some of my mobos -current hangs early (when starning init) if kbdmux is MY> > MY> > MY> > included in kernel (both on i386 and amd64); this seems to be some race, as MY> > MY> > MY> > hangs are not 100% reproducible. What info should I provide to debug? MY> > MY> > MY> MY> > MY> > MY> the usual suspects are MY> > MY> > MY> MY> > MY> > MY> 1) while (KBDMUX_CHECK_CHAR(kbd)) { ... } loop in kbdmux_kbd_event(). MY> > MY> > MY> could you please try to put some debug printf's into it and make sure MY> > MY> > MY> it does not stuck there. MY> > MY> > MY> > MY> > errrm. Added two printfs with ppsratecheck - and, as usual, 'specialist MY> > MY> > presense effect' is in place: no single hang since, both on stock GENERIC and MY> > MY> > my own stripped down kernel so far (approx 20 reboots). MY> > MY> > MY> > MY> > Will try further. MY> > MY> MY> > MY> if you remove your debug code and recompile kbdmux(4), does your MY> > MY> problem re-appear? MY> > MY> > Grrm. It does not (yet). MY> MY> ok. i have to ask. MY> MY> 1) are you using any non-standard compiler options? MY> MY> 2) how are you building new kernel? (or rather do you use NO_CLEAN or MY> something like that?) MY> MY> kbdmux(4) has not been changed for awhile. while i completely accept MY> possibility of bug in kbdmux(4), i find it somewhat strange that it MY> does not manifest itself all the time. 1. CPUTYPE?= on i386 worlds, nothing significant (KERNCONF?= MODULES_OVERRIDE?=) on amd64 2. make buildkernel; I do use NO_CLEAN most of the time, but in these strange cases I blew out /usr/obj/sys completely to make sure there are no leftovers. And remember: the problem did not manifest itself 100% from the beginning. I'll continue to try to reproduce problem. Thanks! Sincerely, D.Marck [DM5020, MCK-RIPE, DM3-RIPN] ------------------------------------------------------------------------ *** Dmitry Morozovsky --- D.Marck --- Wild Woozle --- marck@rinet.ru *** ------------------------------------------------------------------------