tree f20437dc93c8e6bb949c7b6a935b8a2168363122
parent 4418fb6f2495825a133693821daefc211b7aad1c
author Marc Zyngier <marc.zyngier@arm.com> 1527595871 +0100
committer Marc Zyngier <marc.zyngier@arm.com> 1532079284 +0100

arm64: ssbd: Skip apply_ssbd if not using dynamic mitigation

commit 986372c4367f46b34a3c0f6918d7fb95cbdf39d6 upstream.

In order to avoid checking arm64_ssbd_callback_required on each
kernel entry/exit even if no mitigation is required, let's
add yet another alternative that by default jumps over the mitigation,
and that gets nop'ed out if we're doing dynamic mitigation.

Think of it as a poor man's static key...

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