[PATCH 2/3] KVM: arm64: nv: Report addrsz fault at level 0 with a bad VTTBR.BADDR

Zenghui Yu
2026-02-25T17:35:46Z

As per R_BFHQH,

" When an Address size fault is generated, the reported fault code
indicates one of the following:

If the fault was generated due to the TTBR_ELx used in the translation
having nonzero address bits above the OA size, then a fault at level 0. "

Fix the reported Address size fault level as being 0 if the base address is
wrongly programmed by L1.

Fixes: 61e30b9eef7f ("KVM: arm64: nv: Implement nested Stage-2 page table walk logic")
Signed-off-by: Zenghui Yu (Huawei) <zenghui.yu@linux.dev>
---
arch/arm64/kvm/nested.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/kvm/nested.c b/arch/arm64/kvm/nested.c
index 44ed3915b961..a957542ae3c2 100644
--- a/arch/arm64/kvm/nested.c
+++ b/arch/arm64/kvm/nested.c
@@ -280,7 +280,8 @@ static int walk_nested_s2_pgd(struct kvm_vcpu *vcpu, phys_addr_t ipa,
base_addr = wi->baddr & GENMASK_ULL(47, base_lower_bound);

if (check_output_size(wi, base_addr)) {
- out->esr = compute_fsc(level, ESR_ELx_FSC_ADDRSZ);
+ /* R_BFHQH */
+ out->esr = compute_fsc(0, ESR_ELx_FSC_ADDRSZ);
return 1;
}

--
2.53.0