ATA problem in Parallels: warnings -> failures

[Robert Watson]

On Thu, 17 Apr 2008, Robert Watson wrote:

> Since my most recent kernel update, the intermittent TIMEOUT - READ_DMA 
> warnings I get on my parallels install appear to have become somewhat less 
> innocuous:
>
> ad0: TIMEOUT - READ_DMA retrying (1 retry left) LBA=38669679
> ad0: FAILURE - already active DMA on this device
> ad0: setting up DMA failed
> g_vfs_done():ad0s1e[READ(offset=18188230656, length=2048)]error = 5
> cvs update: in directory modules/tx:
> cvs [update aborted]: cannot read CVS/Repository: Input/output error
>
> In the past, this appeared to be a symptom of long and unexplained delays in 
> Parallel's ATA -> image file operation, but were not harmful as the retried 
> operation succeeded.  However, it seems that this is no longer the case, 
> with errors exposed to higher levels of the file system.  Do you have any 
> suggestions?

Your recent commits appear now to have resolved this problem.  I'm still 
getting the usual TIMEOUT's for read and write DMA that I always get in 
Parallels, but no more corrupted UFS, as far as I can tell, anyway. :-)

Thanks,

Robert N M Watson
Computer Laboratory
University of Cambridge