Re: [PATCH][RFC] ServerWorks autodma behavior

[Martin Dalecki <dalecki@evision-ventures.com>]

Ken Brownfield wrote:
> There wasn't a specific MAINTAINER for this stuff, other than perhaps
> Andre Hedrick by proxy, so I decided it might be best to post this
> directly.
> 
> I have a lot of ServerWorks OSB4 IDE hardware, which has the annoyingly
> suboptimal behavior of corrupting filesystems when DMA is active.
> Unfortunately, serverworks.c (in recent 2.4, at least) does not honor
> the CONFIG_IDEDMA_AUTO config option -- it turns dma on only unless
> "ide=nodma" is set on the kernel command line.
> 
> Personally, I think the correct behavior is for the subdrivers to honor
> this config value.  However, only VIA behaves in this way, and PIIX only
> because of its funky CONFIG_PIIX_TUNING config.  This obviates having to
> modify lilo.conf (or similar) on all machines, and having to remember
> to do so, etc etc.
> 
> The alternative is that, somewhat unintuitively, the correct behavior is
> for the subdrivers to make their own non-CONFIGurable decisions on DMA.
> In this case, VIA and PIIX should be corrected, I would think.
> 
> In any case, I've appended the patch I'm using to be able to turn off
> auto-DMA at config-time rather than run-time for ServerWorks.  One
> alternative is to shed this code altogether, since ide-pci.c seems to
> set a rational default.

I think (not 100% becouse not re-checked against the code),
you could just have removed the lines

if (!noautodma)
	hwif->autodma = 1;

and all should be well ;-).