Re: [PATCH] KVM: s390: Cleanup kvm_arch_init error path

[Thomas Huth <thuth@redhat.com>]

On 02/10/2019 10.01, David Hildenbrand wrote:
> On 02.10.19 09:56, Janosch Frank wrote:
>> Both kvm_s390_gib_destroy and debug_unregister test if the needed
>> pointers are not NULL and hence can be called unconditionally.
>>
>> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
>> ---
>>  arch/s390/kvm/kvm-s390.c | 18 +++++++-----------
>>  1 file changed, 7 insertions(+), 11 deletions(-)
>>
>> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
>> index 895fb2006c0d..66720d69cd24 100644
>> --- a/arch/s390/kvm/kvm-s390.c
>> +++ b/arch/s390/kvm/kvm-s390.c
>> @@ -458,16 +458,14 @@ static void kvm_s390_cpu_feat_init(void)
>>  
>>  int kvm_arch_init(void *opaque)
>>  {
>> -	int rc;
>> +	int rc = -ENOMEM;
>>  
>>  	kvm_s390_dbf = debug_register("kvm-trace", 32, 1, 7 * sizeof(long));
>>  	if (!kvm_s390_dbf)
>>  		return -ENOMEM;
>>  
>> -	if (debug_register_view(kvm_s390_dbf, &debug_sprintf_view)) {
>> -		rc = -ENOMEM;
>> -		goto out_debug_unreg;
>> -	}
>> +	if (debug_register_view(kvm_s390_dbf, &debug_sprintf_view))
>> +		goto out;
>>  
>>  	kvm_s390_cpu_feat_init();
>>  
>> @@ -475,19 +473,17 @@ int kvm_arch_init(void *opaque)
>>  	rc = kvm_register_device_ops(&kvm_flic_ops, KVM_DEV_TYPE_FLIC);
>>  	if (rc) {
>>  		pr_err("A FLIC registration call failed with rc=%d\n", rc);
>> -		goto out_debug_unreg;
>> +		goto out;
>>  	}
>>  
>>  	rc = kvm_s390_gib_init(GAL_ISC);
>>  	if (rc)
>> -		goto out_gib_destroy;
>> +		goto out;
>>  
>>  	return 0;
>>  
>> -out_gib_destroy:
>> -	kvm_s390_gib_destroy();
>> -out_debug_unreg:
>> -	debug_unregister(kvm_s390_dbf);
>> +out:
>> +	kvm_arch_exit();
>>  	return rc;
>>  }
> 
> Wonder why "debug_info_t *kvm_s390_dbf" is not declared as static.

Because it is used in the KVM_EVENT macro?

> Instead of the two manual calls we could also call kvm_arch_exit().

Huh, isn't that what this patch is doing here?

To me, the patch is looking fine, so
Reviewed-by: Thomas Huth <thuth@redhat.com>