Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750905AbWJHIOt (ORCPT ); Sun, 8 Oct 2006 04:14:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750906AbWJHIOt (ORCPT ); Sun, 8 Oct 2006 04:14:49 -0400 Received: from 70-91-206-233-BusName-SFBA.hfc.comcastbusiness.net ([70.91.206.233]:61573 "EHLO saville.com") by vger.kernel.org with ESMTP id S1750904AbWJHIOs (ORCPT ); Sun, 8 Oct 2006 04:14:48 -0400 Message-ID: <4528B377.2050104@saville.com> Date: Sun, 08 Oct 2006 01:14:47 -0700 From: Wink Saville User-Agent: Thunderbird 1.5.0.7 (Windows/20060909) MIME-Version: 1.0 To: Andrew Morton CC: Arjan van de Ven , Matthias Hentges , linux-kernel@vger.kernel.org, linux-fbdev-devel@lists.sourceforge.net Subject: Re: Hang in fb_notifier_call_chain with nvidia framebuffer References: <45206777.7020405@saville.com> <1159808447.4652.6.camel@mhcln03> <4521E326.2000406@saville.com> <1159882225.2891.525.camel@laptopd505.fenrus.org> <4523E09C.9000609@saville.com> <20061007230129.323ac807.akpm@osdl.org> In-Reply-To: <20061007230129.323ac807.akpm@osdl.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2620 Lines: 73 Andrew Morton wrote: > On Wed, 04 Oct 2006 09:26:04 -0700 > Wink Saville wrote: > >> Attached in the zip file is: >> >> log-hang1.txt -> log showing hang >> cfg-hang1 -> config file for hang condition >> cfg-ok -> config file that works >> fbmem.c -> Modifications to register_framebuffer >> >> To possibly assist I turned on debugging in nvidia.c and found that it >> hung in the call to register_framebuffer. I then added some additional >> debug in that routine and it appears the hang occurs in the call to >> fb_notifier_call_chain. >> >> Please let me know what else maybe needed. > > Please: > > - get sysrq working: > > set CONFIG_MAGIC_SYSRQ=y, rebuild, reboot > echo 1 > /proc/sys/kernel/sysrq > dmesg -n 8 > > - make it hang > > - Hit alt-sysrq-T > > - Send us the resulting output > > Thanks. > - > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > Andrew, Thank you for the reply, I believe I've found the reason frame buffer doesn't work on my system, there is a divide by zero occurring at line 157 of nvGetClocks in ./drivers/video/nvidia/nv_hw.c. (Note: The screwy output below is due to hacking drivers/serial/8250.c to add two routines serial_putchar and serial_putchars so that I could make progress looking for the bug, as printk stopped working at acquire_console_sem called from bind_con_driver.) Last portion of the output: @[ 97.643286] take_over_console: call bind_con_driver csw=ffffffff805d8600 first=0, last=62, deflt=1 @[ 97.652521] bind_con_driver: E @[ 97.655774] bind_con_driver: acquire_console_sem @1[ 97.660604] acquire_console_sem: drivers/char/vt.c:bind_con_driver:2752 @!2345689abABCDEFabcdefghijabcdbdjklaceiaN=83 NB=0 freq=27000 M=3 MB=0 P=0 >From the above output we see MB=0 and hence death at line 157: *MClk = ((N * NB * par->CrystalFreqKHz) / (M * MB)) >> P; It would seem that my hardware (7600 GT K0) is not supported by the driver? It should also be noted that there are quite a number of divisions in the nv_hw.c that have no protection against divide by zeros. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/