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

From: Dave Hansen
Date: Tue Sep 19 2023 - 12:06:19 EST


On 9/19/23 08:48, Matteo Rizzo wrote:
>> I think the whole "make it one single compile-time option" model is
>> completely and fundamentally broken.
> Wouldn't making this toggleable at boot time or runtime make performance
> even worse?

Maybe.

But you can tolerate even more of a performance impact from a feature if
the people that don't care can actually disable it.

There are also plenty of ways to minimize the overhead of switching it
on and off at runtime. Static branches are your best friend here.