s390/perf: Return error when debug_register fails

[ Upstream commit ec0c0bb489727de0d4dca6a00be6970ab8a3b30a ]

Return an error when the function debug_register() fails allocating
the debug handle.
Also remove the registered debug handle when the initialization fails
later on.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/arch/s390/kernel/perf_cpum_sf.c b/arch/s390/kernel/perf_cpum_sf.c
index b79d514..874762a 100644 (file)
--- a/arch/s390/kernel/perf_cpum_sf.c
+++ b/arch/s390/kernel/perf_cpum_sf.c
@@ -1616,14 +1616,17 @@ static int __init init_cpum_sampling_pmu(void)
        }
 
        sfdbg = debug_register(KMSG_COMPONENT, 2, 1, 80);
-       if (!sfdbg)
+       if (!sfdbg) {
                pr_err("Registering for s390dbf failed\n");
+               return -ENOMEM;
+       }
        debug_register_view(sfdbg, &debug_sprintf_view);
 
        err = register_external_irq(EXT_IRQ_MEASURE_ALERT,
                                    cpumf_measurement_alert);
        if (err) {
                pr_cpumsf_err(RS_INIT_FAILURE_ALRT);
+               debug_unregister(sfdbg);
                goto out;
        }
 
@@ -1632,6 +1635,7 @@ static int __init init_cpum_sampling_pmu(void)
                pr_cpumsf_err(RS_INIT_FAILURE_PERF);
                unregister_external_irq(EXT_IRQ_MEASURE_ALERT,
                                        cpumf_measurement_alert);
+               debug_unregister(sfdbg);
                goto out;
        }
        perf_cpu_notifier(cpumf_pmu_notifier);