Re: [PATCH V3 3/4] dmaselftest: add memcpy selftest support functions

From: Sinan Kaya
Date: Mon Nov 09 2015 - 23:50:09 EST

On 11/9/2015 8:48 AM, Timur Tabi wrote:
Sinan Kaya wrote:

And why kmalloc anyway? Why not leave it on the stack?

char src[] = "hello world";


I need to call dma_map_single on this address to convert it to a DMA
address. That's why.

And you can't do that with an object that's on the stack?

no, pasting from here.

under 'What memory is DMA'able?'

This rule also means that you may use neither kernel image addresses
(items in data/text/bss segments), nor module image addresses, nor
stack addresses for DMA.

Sinan Kaya
Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project
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