Re: [RFC PATCH 00/14] Prevent cross-cache attacks in the SLUB allocator

[Linus Torvalds]

On Mon, 18 Sept 2023 at 10:39, Ingo Molnar <mingo@xxxxxxxxxx> wrote:
>
> What's the split of the increase in overhead due to SLAB_VIRTUAL=y, between
> user-space execution and kernel-space execution?

... and equally importantly, what about DMA?

Or what about the fixed-size slabs (aka kmalloc?) What's the point of
"never re-use the same address for a different slab", when the *same*
slab will contain different kinds of allocations anyway?

I think the whole "make it one single compile-time option" model is
completely and fundamentally broken.

                     Linus