Re: b44 driver causes panic when using swiotlb

From: Andi Kleen
Date: Mon Jan 31 2011 - 11:36:47 EST

On Mon, Jan 31, 2011 at 10:54:12AM -0500, Chuck Ebbert wrote:
> The b44 driver is triggering this panic in swiotlb_map_page():
> if (!dma_capable(dev, dev_addr, size))
> panic("map_single: bounce buffer is not DMA'ble");
> The kernel log says the bounce buffers are at 0xdb400000, but b44 can
> only do DMA to the first 1GB of memory:

b44 needs to use GFP_DMA then and do its own custom bouncing.
The standard pci_map_* bounce buffering is only designed for at least
32bit capable devices.

BTW I'm pretty sure this worked at some point, must have regressed


ak@xxxxxxxxxxxxxxx -- Speaking for myself only
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