linux-kernel - Re: [PATCH 1/3] cyber2000fb: fix machine hang on module load

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Sat, 31 Jul 2010 18:37:27 -0400
From:	Jeff Garzik <jeff@...zik.org>
To:	Russell King - ARM Linux <linux@....linux.org.uk>
CC:	Ondrej Zary <linux@...nbow-software.org>,
	linux-fbdev@...r.kernel.org,
	Kernel development list <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 1/3] cyber2000fb: fix machine hang on module load

On 07/31/2010 05:25 PM, Russell King - ARM Linux wrote:
> On Sat, Jul 31, 2010 at 05:21:33PM -0400, Jeff Garzik wrote:
>> On 07/31/2010 04:55 PM, Ondrej Zary wrote:
>>> I was testing two CyberPro 2000 based PCI cards on x86 and the machine always
>>> hanged completely when the cyber2000fb module was loaded. It seems that the
>>> card hangs when some registers are accessed too quickly after writing RAMDAC
>>> control register. With this patch, both card work.
>>>
>>> Add delay after RAMDAC control register write to prevent hangs on module load.
>>>
>>> Signed-off-by: Ondrej Zary<linux@...nbow-software.org>
>>>
>>> --- linux-2.6.35-rc2-orig/drivers/video/cyber2000fb.c	2010-06-06 05:43:24.000000000 +0200
>>> +++ linux-2.6.35-rc3/drivers/video/cyber2000fb.c	2010-07-27 23:12:37.000000000 +0200
>>> @@ -436,6 +436,8 @@ static void cyber2000fb_write_ramdac_ctr
>>>    	cyber2000fb_writeb(i | 4, 0x3cf, cfb);
>>>    	cyber2000fb_writeb(val, 0x3c6, cfb);
>>>    	cyber2000fb_writeb(i, 0x3cf, cfb);
>>> +	/* prevent card lock-up observed on x86 with CyberPro 2000 */
>>> +	cyber2000fb_readb(0x3cf, cfb);
>>>    }
>>
>> IIRC, cyber2000 is basically an S3 graphics chip.
>
> No such luck.  It's a proprietary Integraphics chip, mainly used in
> ARM Netwinders some 10 years ago.  It's completely different from the
> S3 chips such as Trio64.

Ah, I stand corrected.  Maybe that was cyberfb I was remembering...

	Jeff



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/