[PATCH] perf: qcom_l2_pmu: don't allow guest access

[Neil Leeder]

Guests cannot access IMPDEF system registers, which are used
by this driver. Disable the driver if it's running in a guest VM.

Signed-off-by: Neil Leeder <nleeder@xxxxxxxxxxxxxx>
---
 drivers/perf/qcom_l2_pmu.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/perf/qcom_l2_pmu.c b/drivers/perf/qcom_l2_pmu.c
index 4fdc848..49dc954 100644
--- a/drivers/perf/qcom_l2_pmu.c
+++ b/drivers/perf/qcom_l2_pmu.c
@@ -1057,6 +1057,10 @@ static int __init register_l2_cache_pmu_driver(void)
 {
 	int err;
 
+	/* Don't enable driver if running as guest */
+	if (!is_hyp_mode_available())
+		return 0;
+
 	err = cpuhp_setup_state_multi(CPUHP_AP_PERF_ARM_QCOM_L2_ONLINE,
 				      "AP_PERF_ARM_QCOM_L2_ONLINE",
 				      l2cache_pmu_online_cpu,
-- 
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