diff options
| author | Sascha Bischoff <sascha.bischoff@arm.com> | 2026-10-20 17:39:22 +0100 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2026-10-26 10:57:19 +0000 |
| commit | 05620a31421935f737d16a060d2dfe731f7b2f74 (patch) | |
| tree | 5f8ebc2e24962f2b9b6c3752248e7cffeca9fbbd /include/kvm | |
| parent | 576a1b5ab4b8be03ab5cf7b41b475850795e3fe2 (diff) | |
KVM: arm64: vgic: Require matching VGIC and ITS models
On a GICv5 host with legacy support, KVM registers both VGICv3 and
VGICv5 devices. Without a model check, a VM can create a GICv3 ITS
alongside an incompatible VGIC, regardless of creation order.
The same problem exists for GICv2 on hosts that support a GICv3 ITS.
KVM used to allow userspace to create both devices in either order,
then ignored the ITS.
Record the VGIC model required by an ITS. Reject an ITS if the VM
already has an incompatible VGIC, and reject a VGIC if an existing
ITS requires a different model. These checks apply on every host:
a GICv2 VGIC and a GICv3 ITS now fail with -ENODEV in either order.
Allow either creation order when the models match.
Have vgic_has_its() require matching VGIC and ITS models, and drop
the separate has_its flag.
As part of this change, swap the type of vgic_model from u32 to enum
kvm_device_type. This requires updating the switch cases in
kvm_vgic_vcpu_init() and kvm_vgic_dist_destroy() to include default
cases, which we mark as unreachable().
Signed-off-by: Sascha Bischoff <sascha.bischoff@arm.com>
Reviewed-by: Fuad Tabba <fuad.tabba@linux.dev>
Link: https://patch.msgid.link/20261020163923.1407856-2-sascha.bischoff@arm.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
Diffstat (limited to 'include/kvm')
| -rw-r--r-- | include/kvm/arm_vgic.h | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index 7be81b936bf1..cad74eaff0a7 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -502,7 +502,9 @@ struct vgic_dist { bool initialized; /* vGIC model the kernel emulates for the guest (GICv2 or GICv3) */ - u32 vgic_model; + enum kvm_device_type vgic_model; + /* VGIC model required by the VM's ITS devices. */ + enum kvm_device_type its_model; /* Implementation revision as reported in the GICD_IIDR */ u32 implementation_rev; @@ -547,7 +549,6 @@ struct vgic_dist { struct vgic_io_device dist_iodev; struct vgic_io_device cpuif_iodev; - bool has_its; bool table_write_in_progress; /* |