Commit de5bcdb4 authored by Will Deacon's avatar Will Deacon Committed by Marc Zyngier
Browse files

KVM: arm64: Tidy up kvm_map_vector() 



The bulk of the work in kvm_map_vector() is conditional on the
ARM64_HARDEN_EL2_VECTORS capability, so return early if that is not set
and make the code a bit easier to read.

Signed-off-by: default avatarWill Deacon <will@kernel.org>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Quentin Perret <qperret@google.com>
Link: https://lore.kernel.org/r/20201113113847.21619-3-will@kernel.org
parent 8934c845

arch/arm64/kvm/arm.c

+14 −14
Original line number Diff line number Diff line
@@ -1297,6 +1297,8 @@ static unsigned long nvhe_percpu_order(void) 


static int kvm_map_vectors(void)

{

	int slot;



	/*

	 * SV2  = ARM64_SPECTRE_V2

	 * HEL2 = ARM64_HARDEN_EL2_VECTORS
@@ -1306,22 +1308,20 @@ static int kvm_map_vectors(void) 
	 * !SV2 +  HEL2 -> allocate one vector slot and use exec mapping

	 *  SV2 +  HEL2 -> use hardened vectors and use exec mapping

	 */

	if (cpus_have_const_cap(ARM64_HARDEN_EL2_VECTORS)) {

		phys_addr_t vect_pa = __pa_symbol(__bp_harden_hyp_vecs);

		unsigned long size = __BP_HARDEN_HYP_VECS_SZ;

	if (!cpus_have_const_cap(ARM64_HARDEN_EL2_VECTORS))

		return 0;



	/*

		 * Always allocate a spare vector slot, as we don't

		 * know yet which CPUs have a BP hardening slot that

		 * we can reuse.

	 * Always allocate a spare vector slot, as we don't know yet which CPUs

	 * have a BP hardening slot that we can reuse.

	 */

		__kvm_harden_el2_vector_slot = atomic_inc_return(&arm64_el2_vector_last_slot);

		BUG_ON(__kvm_harden_el2_vector_slot >= BP_HARDEN_EL2_SLOTS);

		return create_hyp_exec_mappings(vect_pa, size,

						&__kvm_bp_vect_base);

	}

	slot = atomic_inc_return(&arm64_el2_vector_last_slot);

	BUG_ON(slot >= BP_HARDEN_EL2_SLOTS);

	__kvm_harden_el2_vector_slot = slot;



	return 0;

	return create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs),

					__BP_HARDEN_HYP_VECS_SZ,

					&__kvm_bp_vect_base);

}



static void cpu_init_hyp_mode(void)