[RFC PATCH v3 6/8] arm64: Add hook for checking early CPU features

Suzuki K. Poulose suzuki.poulose at arm.com
Wed Dec 9 01:57:17 PST 2015

Adds a hook for checking whether a secondary CPU has the
features used already by the kernel during early boot, based
on the boot CPU.

Cc: Will Deacon <will.deacon at arm.com>
Cc: Mark Rutland <mark.rutland at arm.com>
Cc: Catalin Marinas <catalin.marinas at arm.com>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose at arm.com>
 arch/arm64/kernel/cpufeature.c |   10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index b94a198..e63da0f 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -824,6 +824,14 @@ static u64 __raw_read_system_reg(u32 sys_id)
+ * Check for CPU features that are used in early boot
+ * based on the Boot CPU value.
+ */
+static void check_early_cpu_features(void)
  * Run through the enabled system capabilities and enable() it on this CPU.
  * The capabilities were decided based on the available CPUs at the boot time.
  * Any new CPU should match the system wide status of the capability. If the
@@ -836,6 +844,8 @@ void verify_local_cpu_capabilities(void)
 	int i;
 	const struct arm64_cpu_capabilities *caps;
+	check_early_cpu_features();
 	 * If we haven't computed the system capabilities, there is nothing
 	 * to verify.

More information about the linux-arm-kernel mailing list