Re: [PATCH 17/17] arm64: Do not expose PCI mmap through procfs

From: Sinan Kaya
Date: Wed Mar 22 2017 - 10:15:39 EST


On 3/22/2017 10:04 AM, David Woodhouse wrote:
> On Wed, 2017-03-22 at 09:54 -0400, Sinan Kaya wrote:
>> On 3/22/2017 9:25 AM, David Woodhouse wrote:
>>>
>>>
>>> +#ifdef __aarch64__
>>> +/* ARM64 wants to be special and not expose this through /proc
>>> like everyone else */
>>> +#undef HAVE_PCI_MMAP
>>> +#endif
>>> +
>> Where is this ARM64 special requirement coming from?
>
> The idea is that as a new platform, ARM64 shouldn't need to implement
> legacy userspace interfaces.
>
> http://lists.infradead.org/pipermail/linux-arm-kernel/2016-April/422571.html
>

Aren't we breaking an ABI for userspace? I know DPDK relies on this feature.

--
Sinan Kaya
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.