[PATCH v18 07/14] KVM: arm64: Forward GCS exceptions to nested guests
From: Mark Brown <broonie@kernel.org>
Date: 2026-08-03 23:14:08
Also in:
kvmarm, linux-doc, linux-kselftest, lkml
Subsystem:
arm64 port (aarch64 architecture), kernel virtual machine for arm64 (kvm/arm64), the rest · Maintainers:
Catalin Marinas, Will Deacon, Marc Zyngier, Oliver Upton, Linus Torvalds
For nested guests where HFGITR_EL2.nGCSSTR_EL1 is clear or when there are L2 GCS data check exceptions we need to forward the exception to the guest. Add handling to do so. Signed-off-by: Mark Brown <broonie@kernel.org> --- arch/arm64/kvm/handle_exit.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-)
diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c
index 54aedf93c78b..63dcc4a0e69a 100644
--- a/arch/arm64/kvm/handle_exit.c
+++ b/arch/arm64/kvm/handle_exit.c@@ -304,12 +304,24 @@ static int handle_svc(struct kvm_vcpu *vcpu) return 1; } +/* + * We might get GCS exceptions that need to be forwarded to the + * hypervisor when a nested guest has HFGITR_EL2.nGCSSTR_EL1 clear, or + * for a GCS data check exception for a L2 guest. + */ static int kvm_handle_gcs(struct kvm_vcpu *vcpu) { - /* We don't expect GCS, so treat it with contempt */ - if (kvm_has_feat(vcpu->kvm, ID_AA64PFR1_EL1, GCS, IMP)) - WARN_ON_ONCE(1); + if (!kvm_has_gcs(vcpu->kvm)) { + kvm_inject_undefined(vcpu); + return 1; + } + if (vcpu_has_nv(vcpu)) { + kvm_inject_nested_sync(vcpu, kvm_vcpu_get_esr(vcpu)); + return 1; + } + + WARN_ON_ONCE(1); kvm_inject_undefined(vcpu); return 1; }
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2.47.3