Re: [PATCH 09/10] Input: Hold wake lock while event queue is not empty.

Arve Hjønnevåg
2009-02-13T23:51:40Z

On Thu, Feb 12, 2009 at 4:57 PM, Matthew Garrett <mjg59@srcf.ucam.org> wrote:
> On Thu, Feb 12, 2009 at 04:52:22PM -0800, Arve Hjønnevåg wrote:
>
>> That was not the bug. Another component opened one of the input
>> devices, but did not read events from it.
>
> It's not the job of the kernel to guard against userspace doing foolish
> things.

Not true. The kernel in general tries to protect processes from
causing harm to other processes or to the kernel itself.

> Either you want to wait for input events to be consumed before
> suspend or you don't - arbitrary timeouts provide no guarantees about
> the correctness of your platform's behaviour. The default permissions on
> the event devices mean that the only components that could interfere
> with this are ones under your control, so fixing them seems like the
> sensible approach.

We did fix the bug. My point is that is it completely unreasonable for
the user space to code take more than 5 seconds to read an input
event. Trying to protecting the system (not the app) against this is
not unreasonable.

--
Arve Hjønnevåg