If the kernel is not compiled with CONFIG_ARM64_PTR_AUTH_KERNEL=y,
then no PACI/AUTI instructions are expected while the kernel is running
so the kernel's key will not be used. Write of a system registers
is expensive therefore avoid if not required.
Signed-off-by: NDaniel Kiss <daniel.kiss@arm.com>
Reviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210613092632.93591-3-daniel.kiss@arm.comSigned-off-by: NWill Deacon <will@kernel.org>