Re: [PATCH v2 17/20] arm64: bp hardening: Allow late CPUs to enable work around

2018-02-08 Thread Suzuki K Poulose
On 08/02/18 17:59, Suzuki K Poulose wrote: On 08/02/18 16:58, Suzuki K Poulose wrote: On 08/02/18 12:26, Marc Zyngier wrote: On 08/02/18 12:19, Suzuki K Poulose wrote: On 07/02/18 10:39, Dave Martin wrote: On Wed, Jan 31, 2018 at 06:28:04PM +, Suzuki K Poulose wrote: We defend against br

Re: [PATCH v2 17/20] arm64: bp hardening: Allow late CPUs to enable work around

2018-02-08 Thread Suzuki K Poulose
On 08/02/18 16:58, Suzuki K Poulose wrote: On 08/02/18 12:26, Marc Zyngier wrote: On 08/02/18 12:19, Suzuki K Poulose wrote: On 07/02/18 10:39, Dave Martin wrote: On Wed, Jan 31, 2018 at 06:28:04PM +, Suzuki K Poulose wrote: We defend against branch predictor training based exploits by ta

Re: [PATCH v2 17/20] arm64: bp hardening: Allow late CPUs to enable work around

2018-02-08 Thread Suzuki K Poulose
On 08/02/18 12:26, Marc Zyngier wrote: On 08/02/18 12:19, Suzuki K Poulose wrote: On 07/02/18 10:39, Dave Martin wrote: On Wed, Jan 31, 2018 at 06:28:04PM +, Suzuki K Poulose wrote: We defend against branch predictor training based exploits by taking specific actions (based on the CPU mode

Re: [PATCH v2 17/20] arm64: bp hardening: Allow late CPUs to enable work around

2018-02-08 Thread Marc Zyngier
On 08/02/18 12:19, Suzuki K Poulose wrote: > On 07/02/18 10:39, Dave Martin wrote: >> On Wed, Jan 31, 2018 at 06:28:04PM +, Suzuki K Poulose wrote: >>> We defend against branch predictor training based exploits by >>> taking specific actions (based on the CPU model) to invalidate >>> the Branch

Re: [PATCH v2 17/20] arm64: bp hardening: Allow late CPUs to enable work around

2018-02-08 Thread Suzuki K Poulose
On 07/02/18 10:39, Dave Martin wrote: On Wed, Jan 31, 2018 at 06:28:04PM +, Suzuki K Poulose wrote: We defend against branch predictor training based exploits by taking specific actions (based on the CPU model) to invalidate the Branch predictor buffer (BPB). This is implemented by per-CPU p

Re: [PATCH v2 17/20] arm64: bp hardening: Allow late CPUs to enable work around

2018-02-07 Thread Dave Martin
On Wed, Jan 31, 2018 at 06:28:04PM +, Suzuki K Poulose wrote: > We defend against branch predictor training based exploits by > taking specific actions (based on the CPU model) to invalidate > the Branch predictor buffer (BPB). This is implemented by per-CPU > ptr, which installs the specific a

[PATCH v2 17/20] arm64: bp hardening: Allow late CPUs to enable work around

2018-01-31 Thread Suzuki K Poulose
We defend against branch predictor training based exploits by taking specific actions (based on the CPU model) to invalidate the Branch predictor buffer (BPB). This is implemented by per-CPU ptr, which installs the specific actions for the CPU model. The core code can handle the following cases wh