Re: PROBLEM: ide-cd in 2.6.8-2.6.10 and 2.4.26-2.4.28 high cpu use with dma

[Jens Axboe]

On Sun, Jan 09 2005, Alan Cox wrote:
> On Sul, 2005-01-09 at 12:30, Hikaru1@xxxxxxxxxxx wrote:
> > A minor mistake. I forgot to state explicitly that the problem only appears
> > with writing audio cds. Writing data cds does not cause problems.
> 
> It sets the required alignment of buffers for DMA. The 2.6.10 code is
> correct, the question is who is feeding unaligned buffers to the driver
> layer - the kernel or the SG layer. Which burning interface are you
> using  - /dev/sg  (ie dev=1,0,0) or /dev/hd*  (dev=/dev/hdc etc)

Look at the check, it's also doing length check. And for cdda burning,
you are never going to have 32-byte alignment, hence it false back to
pio.

-- 
Jens Axboe

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