RE: [PATCH v4] staging: gdm724x: Fix DMA from stack

Stack allocated buffers cannot be used for DMA
on all architectures so allocate hci_packet buffer
using kmalloc.

I wonder if the usb stack ought/could support a short bounce
buffer within the memory is already has to allocate?

For hci and lengths less than 8 the immediate data can be
placed directly in the ring structure replacing the data
pointer itself.

	David

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On Thu, Feb 11, 2021 at 01:28:41PM +0000, David Laight wrote:

quoted

Stack allocated buffers cannot be used for DMA
on all architectures so allocate hci_packet buffer
using kmalloc.

I wonder if the usb stack ought/could support a short bounce
buffer within the memory is already has to allocate?

No.