From 1dfc3e905089a0bcada268fb5691a605655e0319 Mon Sep 17 00:00:00 2001 From: Oliver Upton Date: Fri, 2 Dec 2022 18:51:56 +0000 Subject: [PATCH] KVM: arm64: Condition HW AF updates on config option As it currently stands, KVM makes use of FEAT_HAFDBS unconditionally. Use of the feature in the rest of the kernel is guarded by an associated Kconfig option. Align KVM with the rest of the kernel and only enable VTCR_HA when ARM64_HW_AFDBM is enabled. This can be helpful for testing changes to the stage-2 access fault path on Armv8.1+ implementations. Link: https://lore.kernel.org/r/20221202185156.696189-7-oliver.upton@linux.dev Signed-off-by: Oliver Upton --- arch/arm64/kvm/hyp/pgtable.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index 30575b5..3d61bd3 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -606,12 +606,14 @@ u64 kvm_get_vtcr(u64 mmfr0, u64 mmfr1, u32 phys_shift) lvls = 2; vtcr |= VTCR_EL2_LVLS_TO_SL0(lvls); +#ifdef CONFIG_ARM64_HW_AFDBM /* * Enable the Hardware Access Flag management, unconditionally * on all CPUs. The features is RES0 on CPUs without the support * and must be ignored by the CPUs. */ vtcr |= VTCR_EL2_HA; +#endif /* CONFIG_ARM64_HW_AFDBM */ /* Set the vmid bits */ vtcr |= (get_vmid_bits(mmfr1) == 16) ? -- 2.7.4