Re: [U-Boot] [RFC PATCH 2/2] ARM: Introduce ability to enable invalidate of BTB on Cortex-A15 for CVE-2017-5715

On 01/26/2018 03:17 AM, Marc Zyngier wrote:

On 25/01/18 21:45, Nishanth Menon wrote:

...

As recommended by Arm in [1], ACR needs to be set[2] to enable invalidation of BTB. This has to be enabled unconditionally for ICIALLU to be functional on Cortex-A15 processors. Provide a config

Not quite. ACTLR[0] (Enable invalidates of BTB) has to be set for the BTB to be invalidated on ICIALLU. ICIALLU itself is always functional (otherwise, we'd have much bigger problems).

Thanks Marc. That did come out completely wrong! Sorry about that. will update once we have kernel side story complete.