drivers/perf: riscv: Return error for default case

If the upper two bits has an invalid valid (0x1), the event mapping
is not reliable as it returns an uninitialized variable.

Return appropriate value for the default case.

Fixes: f0c9363db2dd ("perf/riscv-sbi: Add platform specific firmware event handling")
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Link: https://lore.kernel.org/r/20241212-pmu_event_fixes_v2-v2-2-813e8a4f5962@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

diff --git a/drivers/perf/riscv_pmu_sbi.c b/drivers/perf/riscv_pmu_sbi.c
index 3473ba02abf3cb578ef0f6fe1f564c69080ffdad..da3651d329069c18f54ef4b1615ef908b59c956b 100644 (file)
--- a/drivers/perf/riscv_pmu_sbi.c
+++ b/drivers/perf/riscv_pmu_sbi.c
@@ -507,7 +507,7 @@ static int pmu_sbi_event_map(struct perf_event *event, u64 *econfig)
 {
        u32 type = event->attr.type;
        u64 config = event->attr.config;
-       int ret;
+       int ret = -ENOENT;
 
        /*
         * Ensure we are finished checking standard hardware events for
@@ -551,10 +551,11 @@ static int pmu_sbi_event_map(struct perf_event *event, u64 *econfig)
                        ret = SBI_PMU_EVENT_TYPE_FW << 16 | RISCV_PLAT_FW_EVENT;
                        *econfig = config & RISCV_PMU_PLAT_FW_EVENT_MASK;
                        break;
+               default:
+                       break;
                }
                break;
        default:
-               ret = -ENOENT;
                break;
        }