Re: USB transfer_buffer allocations on 64bit systems

From: Daniel Mack
Date: Fri Apr 09 2010 - 14:09:54 EST


On Fri, Apr 09, 2010 at 12:01:27PM -0400, Alan Stern wrote:
> On Fri, 9 Apr 2010, Pedro Ribeiro wrote:
> > here is the output of the patch you sent me when the interference is triggered.
> >
> > The log is long, 1.3mb in size.
>
> I don't see anything suspicious. The transfer_buffer addresses repeat
> every 32 URBs, and the DMA addresses cycle almost entirely uniformly
> from 0x20000000 to 0x23ffffff in units of 0x2000 (there are a few gaps
> where the interval is a little bigger).

The DMA pointers do indeed look sane. I wanted to take a deeper look at
this and set up a 64bit system today. However, I fail to see the problem
here. Pedro, how much RAM does your machine have installed?

Daniel

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