Re: Macbook Air 6, 2: i915-related interrupt storm after Yosemite update -- resolved

Christian Kastner
2015-02-11T09:43:55Z

On 2014-11-01 18:08, Christian Kastner wrote:
> I have a Macbook Air (2013) (6,2) which until recently was working
> flawlessly with Debian unstable, which I use almost exclusively on that
> machine. I did keep the OSX installation, mainly because it's the only
> way to get firmware updates.
>
> Recently, in a moment of weakness, I said "yes" to the offer of
> upgrading OSX to Yosemite. Since then, whenever I boot Debian, there is
> an i915-related interrupt storm, with a kworker thread constantly
> running at 70%.
>
> Downgrading OSX back to Mavericks did not help. Apparently Yosemite
> included firmware updates, as within OSX I am shown version numbers that
> are so new they aren't even listed on Apple's homepage yet.
>
> Here's what I see:
>
> $ GPE=/sys/firmware/acpi/interrupts/gpe66
> $ while true; doe cat $GPE; sleep 1; done
> 727268 enabled
> 757981 enabled
> 788576 enabled
> 807337 enabled
> 828426 enabled
> ...
>
> I've tested this with 3.16 and 3.17 kernels; I was using the former for
> about a month now without issue.
>
> When I boot with modprobe.blacklist=i915, the issue disappears.
>
> Does anyone have an idea what could be going on?

Good news: the recent update of OSX to 10.10.2 contained another silent
firmware update, and it appears that this update resolved the issue.

Regards,