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-rw-r--r--drivers/perf/arm_spe_pmu.c9
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/perf/arm_spe_pmu.c b/drivers/perf/arm_spe_pmu.c
index 8ce262fc2561..51b40aecb776 100644
--- a/drivers/perf/arm_spe_pmu.c
+++ b/drivers/perf/arm_spe_pmu.c
@@ -1164,6 +1164,15 @@ static int arm_spe_pmu_device_dt_probe(struct platform_device *pdev)
struct arm_spe_pmu *spe_pmu;
struct device *dev = &pdev->dev;
+ /*
+ * If kernelspace is unmapped when running at EL0, then the SPE
+ * buffer will fault and prematurely terminate the AUX session.
+ */
+ if (arm64_kernel_unmapped_at_el0()) {
+ dev_warn_once(dev, "profiling buffer inaccessible. Try passing \"kpti=off\" on the kernel command line\n");
+ return -EPERM;
+ }
+
spe_pmu = devm_kzalloc(dev, sizeof(*spe_pmu), GFP_KERNEL);
if (!spe_pmu) {
dev_err(dev, "failed to allocate spe_pmu\n");

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