Commit 77cb2d91 authored Oct 28, 2015 by Marc Zyngier

arm64: KVM: VHE: Add fpsimd enabling on guest access



Despite the fact that a VHE enabled kernel runs at EL2, it uses
CPACR_EL1 to trap FPSIMD access. Add the required alternative
code to re-enable guest FPSIMD access when it has trapped to
EL2.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

parent 5efe6de1

arch/arm64/kvm/hyp/entry.S

+6 −0

Original line number	Diff line number	Diff line
		@@ -130,9 +130,15 @@ ENDPROC(__guest_exit)
		ENTRY(__fpsimd_guest_restore)
		stp x4, lr, [sp, #-16]!

		alternative_if_not ARM64_HAS_VIRT_HOST_EXTN
		mrs x2, cptr_el2
		bic x2, x2, #CPTR_EL2_TFP
		msr cptr_el2, x2
		alternative_else
		mrs x2, cpacr_el1
		orr x2, x2, #CPACR_EL1_FPEN
		msr cpacr_el1, x2
		alternative_endif
		isb

		mrs x3, tpidr_el2