From owner-freebsd-current@FreeBSD.ORG Sun Sep 28 20:38:28 2014 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 174D9E87 for ; Sun, 28 Sep 2014 20:38:28 +0000 (UTC) Received: from mail-pa0-x22c.google.com (mail-pa0-x22c.google.com [IPv6:2607:f8b0:400e:c03::22c]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id DC2B62EB for ; Sun, 28 Sep 2014 20:38:27 +0000 (UTC) Received: by mail-pa0-f44.google.com with SMTP id et14so1397228pad.31 for ; Sun, 28 Sep 2014 13:38:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=content-type:mime-version:subject:from:in-reply-to:date:cc :message-id:references:to; bh=mEpSxacnES6BvMniDRnL+WQOlntPbdu3eHZkTr/Z5YQ=; b=T5eBC9HhGdSJE4QBcz4/cwzXk5gEWp93o+s7db+IoMM2kbRbJZnuXDYKOXXFTkP7KD wN2betMQUv/LhUx+BWtmgvH1F829ljCpQsI3Tzh3s01p4PwuRkQKJfdGu6qf/5iDX1HN 3YtZkVWf0wMsVusdj2Ns7xc12rzR3XK+X7QzYiM1lXtFpPpUfPNr0KKyRRS4a6sW0c+n UOoJAK8qH95sW9XUstelDlZlHk2ZbLvSs0CXAkMjbZRhEfCh+bgWd0q0PawftPUfH7FG XeMfVXpRzdyAg6p3csBECWXhW0GT6MIj0rbZqz7UYmvLqXXJMKcOQazF+2wxmaZhY+p0 AqrA== X-Received: by 10.66.141.197 with SMTP id rq5mr53702461pab.124.1411936707510; Sun, 28 Sep 2014 13:38:27 -0700 (PDT) Received: from ?IPv6:2601:8:ab80:7d6:b9b6:ae1a:c5f8:5a4? ([2601:8:ab80:7d6:b9b6:ae1a:c5f8:5a4]) by mx.google.com with ESMTPSA id dg9sm10431784pdb.50.2014.09.28.13.38.26 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Sun, 28 Sep 2014 13:38:26 -0700 (PDT) Content-Type: multipart/signed; boundary="Apple-Mail=_C461D4E5-545F-48E9-A3D9-85D515C522E7"; protocol="application/pgp-signature"; micalg=pgp-sha512 Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.6\)) Subject: Re: What do you use for kernel debugging? From: Garrett Cooper In-Reply-To: <20140928071641.M7664@beckpeccoz.com> Date: Sun, 28 Sep 2014 13:38:24 -0700 Message-Id: <761DF16E-5383-46BA-B886-CD3358D976AA@gmail.com> References: <20140928071641.M7664@beckpeccoz.com> To: =?iso-8859-1?Q?Jos=E9_P=E9rez_Arauzo?= X-Mailer: Apple Mail (2.1878.6) Cc: FreeBSD Current X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.18-1 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: Sun, 28 Sep 2014 20:38:28 -0000 --Apple-Mail=_C461D4E5-545F-48E9-A3D9-85D515C522E7 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=windows-1252 On Sep 28, 2014, at 0:34, Jos=E9 P=E9rez Arauzo wrote: > Hello, > I am trying to track down a (deadlock?) issue in CURRENT via DDB. The = kernel does > not complete hw probes on my Acer V5. >=20 > I get stuck on apic_isr looping which leads nowhere. >=20 > So I thought maybe things improve if I debug from another machine. >=20 >=20 > What do you use for kernel debugging? According to the handbook kgdb = over serial > is a good option, do you agree? I'm on a netbook with no ethernet and = no option > for firewire: can I have a USB / nullmodem setup to work? >=20 > I have no old-style uarts hardware anymore, as the handbook = suggests... >=20 > Any idea is welcome before I buy extra hw. I have a USB to serial = showing up as > /dev/cuaU0, do I need to grab another one and a nullmodem cable or = there are better > alternatives? Thank you. There was some discussion recently about this on an internal list. = Unfortunately no, there isn=92t a usable way, but there were some = interesting viable methods that came up (which haven=92t been = implemented): ethernet/sound/xHCI. Your best bet, as others have noted, is to use boot -d, use WITNESS to = spot locking issues, dtrace to isolate which section of code there are = problems, and finally use one of the DEBUG options noted in = /sys/conf/NOTES and /sys//conf/NOTES . Hope that helps! -Garrett --Apple-Mail=_C461D4E5-545F-48E9-A3D9-85D515C522E7 Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename=signature.asc Content-Type: application/pgp-signature; name=signature.asc Content-Description: Message signed with OpenPGP using GPGMail -----BEGIN PGP SIGNATURE----- Comment: GPGTools - https://gpgtools.org iQEcBAEBCgAGBQJUKHHAAAoJEMZr5QU6S73easYIAKdOGhZ3SvgF6FsauvKm1+Qs VTjc6GM52jQ8ph8Xnk51ETnCcCszZOyfG/5pwU9ldh3hiJNLYj1TKuIpxOEtmhX2 u9cyM9fWXRK/VIycFtsdoP3HvEwPRG2SFOUQO5VxVVvwEoGEWD+Jez/7KYm1tadO X4bkKnnXb9wYTz+pJNhXwjdX2Yxfgx+mi8iS2/7YxQgytC89wScoPLrsIEjyGENW iiSSJbbKLduOBvSJWO3aWIeEXItsbR2wJlbMtRPb4sJPk+MN5j9g2b9SElKzBi6m 2I3ZyOAEH0EJJDGsZNJkNZQzQHeFyldaJSBYchVIaKDbPQHiQeqFFxfVkCjJJ/E= =cDlc -----END PGP SIGNATURE----- --Apple-Mail=_C461D4E5-545F-48E9-A3D9-85D515C522E7--