Re: [patch 22/37] arm64: smp: Switch to hotplug core state synchronization

Thomas Gleixner
2023-04-26T08:15:55Z

On Wed, Apr 26 2023 at 08:59, Mark Rutland wrote:
> On Tue, Apr 25, 2023 at 09:51:12PM +0200, Thomas Gleixner wrote:
>> If not then it's just yet another way of DoS which is an "acceptable"
>> attack as it only affects availability but not confidentiality.
>
> Sure.
>
> My thinking is that this is an attack against the *integrity* of the guest
> (since the vCPU that gets unpasued may write to memory), and so it's
> potentially more than just a DoS.
>
> I only mention this because I'd like to account for that on arm64, and if other
> architectures also wanted to handle that it might make sense to have some
> common infrastructure to track whether CPUs are potentially still within the
> kernel.

Fair enough.