Re: [PATCH] task_struct: Only use anon struct under randstruct plugin

[Andrew Morton]

On Tue, 27 Mar 2018 14:36:09 -0700 Kees Cook <keescook@xxxxxxxxxxxx> wrote:

> The original intent for always adding the anonymous struct in task_struct
> was to make sure we had compiler coverage. However, this caused
> pathological padding of 40 bytes at the start of task_struct.

Why?  What caused this padding?  It happens in all configs?

> Instead,
> move the anonymous struct to being only used when struct layout
> randomization is enabled.

So the mysterious 40 byte bloat is still present in this case?

> Reported-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> Fixes: 29e48ce87f1e ("task_struct: Allow randomized")
> Cc: stable@xxxxxxxxxxxxxxx

Why cc:stable?