Re: [patch 2/2] acpi: Avoid dropping rapid hotkey events (or other GPEs) on Asus EeePC

[Alan Jenkins <alan.christopher.jenkins@googlemail.com>]

Alexey Starikovskiy wrote:
> Hi Alan,
> That patch is old news already...
> There is a new shiny one appended to 9998/10724/11549...
> Please give it a try. It does disable GPE, but for very small duration.

Ok.  I was put off by the noise :-).

I've just tested 2.6.27-rc6 with
<http://bugzilla.kernel.org/show_bug.cgi?id=9998#c81>.  It still "drops"
some events, but now it takes longer to happen.  I have to work much
harder bashing the keys to reproduce it.


Like before, missing an event has severe consequences.  The missed event
is buffered.  When a new event occurs, only the oldest event is removed
from the buffer.  Therefore the buffer can only grow.  Eventually,
something breaks.  Events stop being delivered altogether; presumably
the buffer overflows.  I confirmed that this does still happen.

Remember that these are the consequences of a specific EC bug.  On my
EC, querying an event always clears SCI_EVT, even if there are more
events pending.  It is only re-raised when a new event fires.


I'll try reading the patch.  I may try capturing an EC debug log to show
how the event is dropped, but that will take time.

Thanks
Alan