tree 55441f43ee6fcce7a329bb2e810a09b3e04def84
parent c4fe827b65db1561fb25779c98959039f36c767f
author Marc Zyngier <marc.zyngier@arm.com> 1527595872 +0100
committer Marc Zyngier <marc.zyngier@arm.com> 1532079284 +0100

arm64: ssbd: Restore mitigation status on CPU resume

commit 647d0519b53f440a55df163de21c52a8205431cc upstream.

On a system where firmware can dynamically change the state of the
mitigation, the CPU will always come up with the mitigation enabled,
including when coming back from suspend.

If the user has requested "no mitigation" via a command line option,
let's enforce it by calling into the firmware again to disable it.

Similarily, for a resume from hibernate, the mitigation could have
been disabled by the boot kernel. Let's ensure that it is set
back on in that case.

Acked-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>