Subject: [PATCH v2 10/18] KVM: arm64: vgic-v5: Add missing trap handing for NV triage

From: Marc Zyngier <[email-masked]>
Date: Wed, 20 May 2026 10:19:41 +0100

From: Sascha Bischoff <[email-masked]>

As things stand, there is no support for Nested Virt with GICv5 guests
yet. However, this is coming and therefore we need to be able to
correctly triage the traps when running with NV.

Add the missing fgtreg lookups required for that to
triage_sysreg_trap(). These are specific to the FGT regs added as part
of GICv5:
   * ICH_HFGRTR_EL2
   * ICH_HFGWTR_EL2
   * ICH_HFGITR_EL2

Fixes: 9d6d9514c08f "(KVM: arm64: gic-v5: Support GICv5 FGTs & FGUs")
Link: https://sashiko.dev/#/patchset/20260319154937.3619520-1-sascha.bischoff%40arm.com
Signed-off-by: Sascha Bischoff <[email-masked]>
Signed-off-by: Marc Zyngier <[email-masked]>
---
 arch/arm64/kvm/emulate-nested.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/arm64/kvm/emulate-nested.c b/arch/arm64/kvm/emulate-nested.c
index dba7ced74ca5e..a4eb36b4c4421 100644
--- a/arch/arm64/kvm/emulate-nested.c
+++ b/arch/arm64/kvm/emulate-nested.c
@@ -2631,6 +2631,14 @@ bool triage_sysreg_trap(struct kvm_vcpu *vcpu, int *sr_index)
 		fgtreg = HFGITR2_EL2;
 		break;
 
+	case ICH_HFGRTR_GROUP:
+		fgtreg = is_read ? ICH_HFGRTR_EL2 : ICH_HFGWTR_EL2;
+		break;
+
+	case ICH_HFGITR_GROUP:
+		fgtreg = ICH_HFGITR_EL2;
+		break;
+
 	default:
 		/* Something is really wrong, bail out */
 		WARN_ONCE(1, "Bad FGT group (encoding %08x, config %016llx)\n",
-- 
2.47.3