Re: [PATCH] of: set dma_mask to point to coherent_dma_mask

From: Russell King - ARM Linux
Date: Tue Nov 12 2013 - 05:22:27 EST


On Mon, Nov 11, 2013 at 04:59:14PM +0000, Stefano Stabellini wrote:
> On Wed, 6 Nov 2013, Stefano Stabellini wrote:
> > On Sat, 2 Nov 2013, Grant Likely wrote:
> > > On Wed, 30 Oct 2013 00:05:22 -0500, Rob Herring <robherring2@xxxxxxxxx> wrote:
> > > > From: Rob Herring <rob.herring@xxxxxxxxxxx>
> > > >
> > > > Platform devices created by DT code don't initialize dma_mask pointer to
> > > > anything. Set it to coherent_dma_mask by default if the architecture
> > > > code has not set it.
> > > >
> > > > Signed-off-by: Rob Herring <rob.herring@xxxxxxxxxxx>
> > >
> > > I believe this is okay. I haven't done any testing to back up that
> > > opinion though.
> >
> > Tested-by: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>
>
> BTW I hope you are planning on sending this upstream soon, because
> without it I can very easily corrupt my root fs by simply booting the system.

What's the mechanism for that corruption? Having the DMA mask not set
should not cause DMA corruption - that hints at something else being
wrong, and that needs to be investigated.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/