From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753660Ab0CZKya (ORCPT ); Fri, 26 Mar 2010 06:54:30 -0400 Received: from chilli.pcug.org.au ([203.10.76.44]:42019 "EHLO smtps.tip.net.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753562Ab0CZKy1 (ORCPT ); Fri, 26 Mar 2010 06:54:27 -0400 Date: Fri, 26 Mar 2010 21:54:16 +1100 From: Stephen Rothwell To: Amit Shah Cc: Sachin Sant , Greg Kroah-Hartman , a.p.zijlstra@chello.nl, Rusty Russell , linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, Anton Blanchard , tglx@linutronix.de, Linus Torvalds , mingo@elte.hu, Alan Cox Subject: Re: [PATCH 4/7] hvc_console: Fix race between hvc_close and hvc_remove Message-Id: <20100326215416.80d09610.sfr@canb.auug.org.au> In-Reply-To: <20100326095821.GA7039@amit-x200.redhat.com> References: <20100319151326.GC8541@kroah.com> <1269011916-8836-4-git-send-email-gregkh@suse.de> <1269119079.8599.65.camel@pasglop> <20100321043725.GA21566@amit-x200.redhat.com> <20100324121902.GJ15789@amit-x200.redhat.com> <4BAC7AD4.4030309@in.ibm.com> <20100326095821.GA7039@amit-x200.redhat.com> X-Mailer: Sylpheed 3.0.1 (GTK+ 2.18.9; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: multipart/signed; protocol="application/pgp-signature"; micalg="PGP-SHA1"; boundary="Signature=_Fri__26_Mar_2010_21_54_16_+1100_YZLZJcjnOWU7PRW3" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --Signature=_Fri__26_Mar_2010_21_54_16_+1100_YZLZJcjnOWU7PRW3 Content-Type: text/plain; charset=US-ASCII Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi Amit, On Fri, 26 Mar 2010 15:28:21 +0530 Amit Shah wrote: > > On (Fri) Mar 26 2010 [14:43:56], Sachin Sant wrote: > > > > I too ran into this issue as reported by Anton. Unfortunately in my > > case the following suggested patch does not help boot the powerpc > > box successfully. The boot still hangs with following messages I have been getting this on my linux-next boot tests for a while as well. > Was the hang you saw before applying this patch at the same place / for > the same reason? I get the same hangs with and without the patch. Paulus bisected it (again) to the commit below and reverting that commit fixes the problem. > OK, this gets even murkier. I don't know why taking a few krefs modifies > hvc_console behaviour to such an extent. >=20 > > Just to confirm i too am facing same issue as reported by Anton, > > reverted commit e74d098c66543d0731de62eb747ccd5b636a6f4c and that allow= ed > > by box to boot successfully. >=20 > Which module uses hvc_console in your case? I assume hcv_vio. I also tested using "init=3D/bin/bash" as a kernel command line option and the console worked while I was running bash, but everything was very sluggish. Then when I did "exec /sbin/init" the console hung completely - sysrq (^O) didn't even work any more (it did while I was running bash). --=20 Cheers, Stephen Rothwell sfr@canb.auug.org.au http://www.canb.auug.org.au/~sfr/ --Signature=_Fri__26_Mar_2010_21_54_16_+1100_YZLZJcjnOWU7PRW3 Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iEYEARECAAYFAkusklgACgkQjjKRsyhoI8z2rgCfdQK7HbJ3o86vDpbSbghLmQwd 7CEAoI4ZvlWTUDm4FooAu/N5fA3VfHXg =wzAl -----END PGP SIGNATURE----- --Signature=_Fri__26_Mar_2010_21_54_16_+1100_YZLZJcjnOWU7PRW3-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtps.tip.net.au (chilli.pcug.org.au [203.10.76.44]) by ozlabs.org (Postfix) with ESMTP id F248DB7CE7 for ; Fri, 26 Mar 2010 21:54:25 +1100 (EST) Date: Fri, 26 Mar 2010 21:54:16 +1100 From: Stephen Rothwell To: Amit Shah Subject: Re: [PATCH 4/7] hvc_console: Fix race between hvc_close and hvc_remove Message-Id: <20100326215416.80d09610.sfr@canb.auug.org.au> In-Reply-To: <20100326095821.GA7039@amit-x200.redhat.com> References: <20100319151326.GC8541@kroah.com> <1269011916-8836-4-git-send-email-gregkh@suse.de> <1269119079.8599.65.camel@pasglop> <20100321043725.GA21566@amit-x200.redhat.com> <20100324121902.GJ15789@amit-x200.redhat.com> <4BAC7AD4.4030309@in.ibm.com> <20100326095821.GA7039@amit-x200.redhat.com> Mime-Version: 1.0 Content-Type: multipart/signed; protocol="application/pgp-signature"; micalg="PGP-SHA1"; boundary="Signature=_Fri__26_Mar_2010_21_54_16_+1100_YZLZJcjnOWU7PRW3" Cc: Greg Kroah-Hartman , a.p.zijlstra@chello.nl, Rusty Russell , linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, Anton Blanchard , tglx@linutronix.de, Linus Torvalds , mingo@elte.hu, Alan Cox List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , --Signature=_Fri__26_Mar_2010_21_54_16_+1100_YZLZJcjnOWU7PRW3 Content-Type: text/plain; charset=US-ASCII Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi Amit, On Fri, 26 Mar 2010 15:28:21 +0530 Amit Shah wrote: > > On (Fri) Mar 26 2010 [14:43:56], Sachin Sant wrote: > > > > I too ran into this issue as reported by Anton. Unfortunately in my > > case the following suggested patch does not help boot the powerpc > > box successfully. The boot still hangs with following messages I have been getting this on my linux-next boot tests for a while as well. > Was the hang you saw before applying this patch at the same place / for > the same reason? I get the same hangs with and without the patch. Paulus bisected it (again) to the commit below and reverting that commit fixes the problem. > OK, this gets even murkier. I don't know why taking a few krefs modifies > hvc_console behaviour to such an extent. >=20 > > Just to confirm i too am facing same issue as reported by Anton, > > reverted commit e74d098c66543d0731de62eb747ccd5b636a6f4c and that allow= ed > > by box to boot successfully. >=20 > Which module uses hvc_console in your case? I assume hcv_vio. I also tested using "init=3D/bin/bash" as a kernel command line option and the console worked while I was running bash, but everything was very sluggish. Then when I did "exec /sbin/init" the console hung completely - sysrq (^O) didn't even work any more (it did while I was running bash). --=20 Cheers, Stephen Rothwell sfr@canb.auug.org.au http://www.canb.auug.org.au/~sfr/ --Signature=_Fri__26_Mar_2010_21_54_16_+1100_YZLZJcjnOWU7PRW3 Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iEYEARECAAYFAkusklgACgkQjjKRsyhoI8z2rgCfdQK7HbJ3o86vDpbSbghLmQwd 7CEAoI4ZvlWTUDm4FooAu/N5fA3VfHXg =wzAl -----END PGP SIGNATURE----- --Signature=_Fri__26_Mar_2010_21_54_16_+1100_YZLZJcjnOWU7PRW3--