From owner-freebsd-current@FreeBSD.ORG Mon Oct 4 23:08:39 2010 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 BDA90106566B for ; Mon, 4 Oct 2010 23:08:39 +0000 (UTC) (envelope-from david@catwhisker.org) Received: from albert.catwhisker.org (m209-73.dsl.rawbw.com [198.144.209.73]) by mx1.freebsd.org (Postfix) with ESMTP id 75E5E8FC13 for ; Mon, 4 Oct 2010 23:08:39 +0000 (UTC) Received: from albert.catwhisker.org (localhost [127.0.0.1]) by albert.catwhisker.org (8.14.4/8.14.4) with ESMTP id o94N8c2a012455; Mon, 4 Oct 2010 16:08:38 -0700 (PDT) (envelope-from david@albert.catwhisker.org) Received: (from david@localhost) by albert.catwhisker.org (8.14.4/8.14.4/Submit) id o94N8cfJ012454; Mon, 4 Oct 2010 16:08:38 -0700 (PDT) (envelope-from david) Date: Mon, 4 Oct 2010 16:08:38 -0700 From: David Wolfskill To: Brandon Gooch Message-ID: <20101004230838.GM1410@albert.catwhisker.org> Mail-Followup-To: David Wolfskill , Brandon Gooch , current@freebsd.org References: <20101001212038.GE1535@albert.catwhisker.org> <20101001233001.GG1535@albert.catwhisker.org> <20101002013344.GI1535@albert.catwhisker.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="tDYGg60iReQ7u8wj" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.3i Cc: current@freebsd.org Subject: Re: Hang near end of kernel probes since r213267 (likely earlier) 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: Mon, 04 Oct 2010 23:08:39 -0000 --tDYGg60iReQ7u8wj Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Oct 01, 2010 at 08:56:13PM -0500, Brandon Gooch wrote: > On Fri, Oct 1, 2010 at 8:33 PM, David Wolfskill wr= ote: > > On Fri, Oct 01, 2010 at 04:30:01PM -0700, David Wolfskill wrote: > >> ... > >> I found the disabling the "Module Bay" appears to avoid the hang -- > >> reliably. > >> > >> That appears to be the minimally-invasive change necessary to avoid the > >> hang. > >> .... > > > > Until I realized what was in the Modular Bay: the CD/CVD reader/burner. > > > > So I tried a variation on the theme: =A0I left all the devices enabled, > > but I physically removed the device from the bay before booting -- and > > was unable to get it to fail. > > > > And -- just now -- I disabled the channel (via atacontrol(8)), inserted > > the drive, and enabled the channel: > ... > If you haven't already, it may be worth trying 'options ATA_CAM' in > your kernel config. As an illustration of the expression "a little knowledge is a dangerous thing," I relay the results of a recent experiment. The hardware on the laptop is AHCI-capable; after reading a bit (and recalling that fact about the hardware), then noting that my kernel config didn't include "device ahci", I tried loading ahci via /boot/loader.conf. I was pleased to note that the same device names were use as with ATA_CAM (disk drive was /dev/ada0), so no further change was needed to fstab. More to the point, I rebooted the machine at least 10 times in succession, and (again, so far!) was unable to re-create the "hang". I am still somewhat concerned that there may be a rather nasty issue with order-of-operations -- at least, in some cases -- and I'm quite willing to help identify the problem and test fixes. But so far, it *appears* that letting the ahci(4) driver attach may avoid the problem. Peace, david --=20 David H. Wolfskill david@catwhisker.org Depriving a girl or boy of an opportunity for education is evil. See http://www.catwhisker.org/~david/publickey.gpg for my public key. --tDYGg60iReQ7u8wj Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.16 (FreeBSD) iEYEARECAAYFAkyqXhIACgkQmprOCmdXAD3MwgCfTnCtK/aycbofryrq2CsYmL/8 /4IAn2C/zCmOZqqjd/Sp3r4K6WVu6ati =XZCq -----END PGP SIGNATURE----- --tDYGg60iReQ7u8wj--