Re: [PATCH v8 00/13] Add Broadcom VK driver

From: Scott Branden
Date: Tue Jan 19 2021 - 15:23:33 EST


Hi Greg,

On 2021-01-18 3:06 p.m., Olof Johansson wrote:
> On Sun, Jan 17, 2021 at 11:17 PM Greg Kroah-Hartman
> <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>> On Sun, Jan 17, 2021 at 10:47:59AM -0800, Olof Johansson wrote:
>>> Hi,
>>>
>>> On Mon, Nov 30, 2020 at 10:42 AM Scott Branden
>>> <scott.branden@xxxxxxxxxxxx> wrote:
>>>> This patch series drops previous patches in [1]
>>>> that were incorporated by Kees Cook into patch series
>>>> "Introduce partial kernel_read_file() support" [2].
>>>>
>>>> Remaining patches are contained in this series to add Broadcom VK driver.
>>>> (which depends on request_firmware_into_buf API addition which has
>>>> now been accepted into the upstream kernel as of v5.10-rc1).
>>>>
>>>> [1] https://lore.kernel.org/lkml/20200706232309.12010-1-scott.branden@xxxxxxxxxxxx/
>>>> [2] https://lore.kernel.org/lkml/20201002173828.2099543-1-keescook@xxxxxxxxxxxx/
>>>
>>> I've been following this series for some time, and I think the code is
>>> ready to go in.
>>>
>>> Greg, mind queuing this up in the misc tree?
>> I will need a new version, this is long gone from my queue.
> I'll let Scott repost then (with acks applied etc)
I can send another patch version with Olof's acks applied to each patch.
Please let me know if that is what you are looking for?
>
>> And hopefully the tty layer abuse is gone... :)
> There's a simple tty driver as the final patch in the series, but it's
> pretty straightforward.
>
> If you've still got concerns with it, the rest of the series should
> stand on its own and should be mergeable without that piece.
Yes, I placed the patch at the end of the series so it can be dropped
if that is what is required to accept the rest of the patches.

There has been no viable solution suggested for replacing this functionality.
We need a tty-like interface that works via access to the circular buffers
in PCIe BAR space and interrupts.

The vk tty devices are a direct replacement to attaching serial cables.
In real production environment it is not possible to attach such cables.

I can work on an alternative tty solution and send such patch later
but I don't know what is going to prevent the tty "abuse".
>
>
> -Olof
Regards,
Scott