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Date: Sat, 5 Mar 2005 15:58:26 -0800 (PST)
From: Rob <spamrefuse@yahoo.com>
To: FreeBSD questions <freebsd-questions@freebsd.org>
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Subject: Re: dma/sysctl
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Luciano Musacchio wrote:
> Hi,
> I've a fbsd machine that hangs once in a while,
> I've this en /var/log/messages:
> ...
> Mar  5 14:44:58 chiba kernel: ad2: WARNING -
>   WRITE_DMA UDMA ICRC error (retrying request)
>   LBA=2949471
> ...
> 
> So, this means my hd is about to crash?
> How can I tell the kernel to reboot on such cases?
> (via sysctl?)

This is 5.3, right? I bet you would not have such
problems with 4.X.

My PC instantly crashed at boot with this same
message. I solved it by adding following to
/boot/loader.conf:
   hw.ata.ata_dma="0"

This will force the harddisk to operate in slow
PIO4 mode, but in my case the DMA trouble disappeared.

Rob.


	
		
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