[Cake] Heaps of cake

[Kevin Darbyshire-Bryant]

On 29/05/16 03:32, Jonathan Morton wrote:
>
>> On 21 May, 2016, at 01:07, Jonathan Morton <chromatix99 at gmail.com> wrote:
>>
>> Please do hammer on these codepaths for all you’re worth.  It compiles and survives a smoke-test, that’s all I know so far.
>
> Having noted a series of kernel panics in cake_drop(), I eventually traced the fault to dequeue_head(), which AFAIK hadn’t been touched since the first version (as it was lifted from fq_codel).  If it’s called on en empty subqueue, it tried to read NULL->next.
>
> The question remains why cake_drop() would select an empty subqueue as the longest one - evidently there’s a missing heap update somewhere.  But at least now it won’t crash if that happens.
>
>   - Jonathan Morton

Pointed my build at the latest code, so far no unexpected out-to-lunch 
moments :-)

Thanks for continuing to work on making things stable again.

Kevin