Re: [PATCH v4 21/21] arm64: cpufeatures: Allow disabling of Pointer Auth from the command-line

Srinivas Ramana
2021-01-27T03:18:16Z

Hi Marc,

On 1/23/2021 6:28 AM, Catalin Marinas wrote:
> On Mon, Jan 18, 2021 at 09:45:33AM +0000, Marc Zyngier wrote:
>> In order to be able to disable Pointer Authentication at runtime,
>> whether it is for testing purposes, or to work around HW issues,
>> let's add support for overriding the ID_AA64ISAR1_EL1.{GPI,GPA,API,APA}
>> fields.
>>
>> This is further mapped on the arm64.nopauth command-line alias.
>>
>> Signed-off-by: Marc Zyngier <maz@kernel.org>
> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>

Verified this Series for PAC control feature from command line. with
arm64.nopauth, we could see PAUTH is disabled on both primary and
secondary cores as expected.

HWCAPs show no PAC support and kernel instructions are being treated as
NOPs.

Tested-by: Srinivas Ramana <sramana@codeaurora.org>