Since number of context-aware breakpoints must be no more than number
of supported breakpoints according to Arm ARM, return an error if
userspace tries to set CTX_CMPS field to such value.
Signed-off-by: Jing Zhang <jingzhangos@xxxxxxxxxx>
---
arch/arm64/kvm/sys_regs.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 50d4e25f42d3..a6299c796d03 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -1539,9 +1539,14 @@ static int set_id_aa64dfr0_el1(struct kvm_vcpu *vcpu,
const struct sys_reg_desc *rd,
u64 val)
{
- u8 pmuver, host_pmuver;
+ u8 pmuver, host_pmuver, brps, ctx_cmps;
bool valid_pmu;
+ brps = FIELD_GET(ID_AA64DFR0_EL1_BRPs_MASK, val);
+ ctx_cmps = FIELD_GET(ID_AA64DFR0_EL1_CTX_CMPs_MASK, val);
+ if (ctx_cmps > brps)
+ return -EINVAL;
+
host_pmuver = kvm_arm_pmu_get_pmuver_limit();
/*
@@ -2061,7 +2066,7 @@ static const struct sys_reg_desc sys_reg_descs[] = {
.get_user = get_id_reg,
.set_user = set_id_aa64dfr0_el1,
.reset = read_sanitised_id_aa64dfr0_el1,
- .val = ID_AA64DFR0_EL1_PMUVer_MASK, },
+ .val = GENMASK(63, 0), },
ID_SANITISED(ID_AA64DFR1_EL1),
ID_UNALLOCATED(5,2),
ID_UNALLOCATED(5,3),
--
2.41.0.rc0.172.g3f132b7071-goog
