ccd on NATA problem - ata0: FAILURE - oversized DMA transfer attempt 73728 > 65536

[YONETANI Tomokazu]

On Wed, Jul 18, 2007 at 09:23:17PM -0700, Matthew Dillon wrote:
>     Please test this patch.  It survived a couple of a buildworld runs
>     on my test box with the chunk size forced to 4K but it does mess
>     with low level disk I/O so make sure anything important is backed up
>     first.

Ok, I tried the patched kernel, with a modification to ata-dma.c to
reduce max DMA size of the second channel to 16k.  ccd devices span
on these two channels, and one of them is used as /usr/obj and another
for /home.  I observed no errors during `make -sj3 buildworld'.  I also
 tried to enlarge the stripe size from 1152 to 64k, but newfs barfed
on it (Invalid argument), so I could only use 65535.

Cheers.

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