[PATCH v2 07/15] KVM: arm64: nv: Save guest's ZCR_EL2 when in hyp context

[Oliver Upton <oliver.upton@linux.dev>]

When running a guest hypervisor, ZCR_EL2 is an alias for the counterpart
EL1 state.

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
---
 arch/arm64/kvm/fpsimd.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/kvm/fpsimd.c b/arch/arm64/kvm/fpsimd.c
index 1807d3a79a8a..53168bbea8a7 100644
--- a/arch/arm64/kvm/fpsimd.c
+++ b/arch/arm64/kvm/fpsimd.c
@@ -173,7 +173,16 @@ void kvm_arch_vcpu_put_fp(struct kvm_vcpu *vcpu)
 
 	if (guest_owns_fp_regs()) {
 		if (vcpu_has_sve(vcpu)) {
-			__vcpu_sys_reg(vcpu, ZCR_EL1) = read_sysreg_el1(SYS_ZCR);
+			u64 zcr = read_sysreg_el1(SYS_ZCR);
+
+			/*
+			 * If the vCPU is in the hyp context then ZCR_EL1 is
+			 * loaded with its vEL2 counterpart.
+			 */
+			if (is_hyp_ctxt(vcpu))
+				__vcpu_sys_reg(vcpu, ZCR_EL2) = zcr;
+			else
+				__vcpu_sys_reg(vcpu, ZCR_EL1) = zcr;
 
 			/*
 			 * Restore the VL that was saved when bound to the CPU,
-- 
2.45.2.627.g7a2c4fd464-goog