On Wed, Mar 27, 2013 at 09:31:33AM -0700, Greg KH wrote:
> On Wed, Mar 27, 2013 at 05:21:13PM +0100, Michael Grzeschik wrote:
> > The udc uses an shared dma memory space between hard and software. This
> > memory layout is described in ci13xxx_qh and ci13xxx_td which are marked
> > with the attribute ((packed)).
> >
> > The compiler currently does not know about the alignment of the memory
> > layout, and will create strb and ldrb operations.
> >
> > The Datasheet of the synopsys core describes, that some operations on
> > the mapped memory need to be atomic double word operations. I.e. the
> > next pointer addressing in the qhead, as otherwise the hardware could
this should be "will" --->^^^^^
> > read wrong data and totally stuck.
> >
> > This patch adds the attribute ((aligned(4))) to the structures to tell
> > the compiler to use 32bit operations. It also adds an wmb() for the
> > prepared TD data before it gets enqueued into the qhead.
> >
> > Cc: stable <[email protected]>
>
> How does this (and the other patches in this series) meet the
> stable_kernel_rules.txt requirements?
Beside the other patches, this one meets the requirements. I will reword
that patch, leave the "Cc: stable" in it, remove it from the others and
repost the series.
Thanks,
Michael
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