Re: [PATCH][RFC] ServerWorks autodma behavior

[Alan Cox]

> I have a lot of ServerWorks OSB4 IDE hardware, which has the annoyingly
> suboptimal behavior of corrupting filesystems when DMA is active.

With newer kernels you should get a panic because we spot the "I'm going
to get 4 bytes stuck in the FIFO and DMA your inodes shifted 4 bytes down the
disk behaviour" - at least in the cases I could study

What set up do you have ?

> 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.

You actually really to just turn off UDMA from experience.

>  	if (hwif->dma_base) {
> +#ifdef CONFIG_IDEDMA_AUTO
>  		if (!noautodma)
>  			hwif->autodma = 1;
> +#endif

I would have expected this to be a fix in the core code to ignore
hwif->autodma but I'll admit I've not looked to see if that is practical.