From 59d78a2ec0e9cfba5935f3a0d3f14a771461cded Mon Sep 17 00:00:00 2001 From: Nianyao Tang Date: Tue, 20 Dec 2022 18:50:24 +0800 Subject: [PATCH] KVM: arm64: Synchronize SMEN on vcpu schedule out If we have VHE and need to reenable SME for host in kvm_arch_vcpu_put_fp, CPACR.SMEN is modified from 0 to 1. Trap control for reading SVCR is modified from enable to disable. Synchronization is needed before reading SVCR later in fpsimd_save, or it may cause sync exception which can not be handled by host. Cc: Marc Zyngier Cc: James Morse Cc: Alexandru Elisei Cc: Suzuki K Poulose Cc: Oliver Upton Cc: Catalin Marinas Cc: Will Deacon Signed-off-by: Nianyao Tang Reviewed-by: Mark Brown Link: https://lore.kernel.org/r/20221220105024.13484-1-dongbo4@huawei.com Signed-off-by: Oliver Upton --- arch/arm64/kvm/fpsimd.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/kvm/fpsimd.c b/arch/arm64/kvm/fpsimd.c index 02dd7e9ebd391..f5799f5713172 100644 --- a/arch/arm64/kvm/fpsimd.c +++ b/arch/arm64/kvm/fpsimd.c @@ -184,6 +184,7 @@ void kvm_arch_vcpu_put_fp(struct kvm_vcpu *vcpu) sysreg_clear_set(CPACR_EL1, CPACR_EL1_SMEN_EL0EN, CPACR_EL1_SMEN_EL1EN); + isb(); } if (vcpu->arch.fp_state == FP_STATE_GUEST_OWNED) { -- 2.30.2