On 10/13/2023 12:48 PM, Dan Carpenter wrote:
> Some of the error paths in this function return don't initialize the
> error code. Return -ENODEV.
>
> Fixes: d6389d3ccc13 ("perf/x86/amd/uncore: Refactor uncore management")
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> ---
> arch/x86/events/amd/uncore.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/events/amd/uncore.c b/arch/x86/events/amd/uncore.c
> index 9b444ce24108..a389828f378c 100644
> --- a/arch/x86/events/amd/uncore.c
> +++ b/arch/x86/events/amd/uncore.c
> @@ -1009,7 +1009,8 @@ static struct amd_uncore uncores[UNCORE_TYPE_MAX] = {
> static int __init amd_uncore_init(void)
> {
> struct amd_uncore *uncore;
> - int ret, i;
> + int ret = -ENODEV;
> + int i;
>
> if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
> boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
Thanks for catching this. I see that 'ret' remains uninitialized for cases
where the hotplug callback registration fails and was thinking if the
following is a better fix for this as the reason might not be ENODEV.
diff --git a/arch/x86/events/amd/uncore.c b/arch/x86/events/amd/uncore.c
index 91f01d6c8f7d..7d768dd01522 100644
--- a/arch/x86/events/amd/uncore.c
+++ b/arch/x86/events/amd/uncore.c
@@ -1039,20 +1039,25 @@ static int __init amd_uncore_init(void)
/*
* Install callbacks. Core will call them for each online cpu.
*/
- if (cpuhp_setup_state(CPUHP_PERF_X86_AMD_UNCORE_PREP,
- "perf/x86/amd/uncore:prepare",
- NULL, amd_uncore_cpu_dead))
+ ret = cpuhp_setup_state(CPUHP_PERF_X86_AMD_UNCORE_PREP,
+ "perf/x86/amd/uncore:prepare",
+ NULL, amd_uncore_cpu_dead);
+ if (ret)
goto fail;
- if (cpuhp_setup_state(CPUHP_AP_PERF_X86_AMD_UNCORE_STARTING,
- "perf/x86/amd/uncore:starting",
- amd_uncore_cpu_starting, NULL))
+ ret = cpuhp_setup_state(CPUHP_AP_PERF_X86_AMD_UNCORE_STARTING,
+ "perf/x86/amd/uncore:starting",
+ amd_uncore_cpu_starting, NULL);
+ if (ret)
goto fail_prep;
- if (cpuhp_setup_state(CPUHP_AP_PERF_X86_AMD_UNCORE_ONLINE,
- "perf/x86/amd/uncore:online",
- amd_uncore_cpu_online,
- amd_uncore_cpu_down_prepare))
+
+ ret = cpuhp_setup_state(CPUHP_AP_PERF_X86_AMD_UNCORE_ONLINE,
+ "perf/x86/amd/uncore:online",
+ amd_uncore_cpu_online,
+ amd_uncore_cpu_down_prepare);
+ if (ret)
goto fail_start;
+
return 0;
fail_start:
