[PATCH v2 3/9] arm64: KVM: PMU: Inject UNDEF on non-privileged accesses

Marc Zyngier
2017-03-27T16:02:07Z

access_pminten() and access_pmuserenr() can only be accessed when
the CPU is in a priviledged mode. If it is not, let's inject an
UNDEF exception.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/arm64/kvm/sys_regs.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index d98ce9a52291..5e3ce7890b35 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -709,8 +709,10 @@ static bool access_pminten(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
if (!kvm_arm_pmu_v3_ready(vcpu))
return trap_raz_wi(vcpu, p, r);

- if (!vcpu_mode_priv(vcpu))
+ if (!vcpu_mode_priv(vcpu)) {
+ kvm_inject_undefined(vcpu);
return false;
+ }

if (p->is_write) {
u64 val = p->regval & mask;
@@ -780,8 +782,10 @@ static bool access_pmuserenr(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
return trap_raz_wi(vcpu, p, r);

if (p->is_write) {
- if (!vcpu_mode_priv(vcpu))
+ if (!vcpu_mode_priv(vcpu)) {
+ kvm_inject_undefined(vcpu);
return false;
+ }

vcpu_sys_reg(vcpu, PMUSERENR_EL0) = p->regval
& ARMV8_PMU_USERENR_MASK;
--
2.11.0