[PATCH v2 06/45] KVM: arm64: Make MPAMSM_EL1 accesses UNDEF

Ben Horgan
2025-12-19T18:12:31Z

The MPAMSM_EL1 controls the MPAM labeling for an SMCU, Streaming Mode
Compute Unit. As there is on MPAM support in kvm, make sure MPAMSM_EL1
accesses trigger an UNDEF.

The range of valid configurations for the PARTID and PMG in MPAMSM_EL1 is
not currently specified in Arm Architectural Reference Manual but the
architect has confirmed that it is intended to be the same as that for the
cpu configuration in the MPAMy_ELx registers.

Signed-off-by: Ben Horgan <ben.horgan@arm.com>
---
arch/arm64/kvm/sys_regs.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index c8fd7c6a12a1..72654ab984ee 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -3373,6 +3373,8 @@ static const struct sys_reg_desc sys_reg_descs[] = {

{ SYS_DESC(SYS_MPAM1_EL1), undef_access },
{ SYS_DESC(SYS_MPAM0_EL1), undef_access },
+ { SYS_DESC(SYS_MPAMSM_EL1), undef_access },
+
{ SYS_DESC(SYS_VBAR_EL1), access_rw, reset_val, VBAR_EL1, 0 },
{ SYS_DESC(SYS_DISR_EL1), NULL, reset_val, DISR_EL1, 0 },

--
2.43.0