diff options
Diffstat (limited to 'drivers/perf/arm_spe_pmu.c')
| -rw-r--r-- | drivers/perf/arm_spe_pmu.c | 9 |
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"); |