Re: [PATCH 3.12-rc7] KVM: Fix modprobe failure for kvm_intel/kvm_amd

[Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>]

On 10/30/2013 07:53 PM, Greg KH wrote:
[...]
>>
>> diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
>> index a0e2a8a..e475fdb 100644
>> --- a/arch/x86/kernel/kvm.c
>> +++ b/arch/x86/kernel/kvm.c
>> @@ -622,7 +622,7 @@ static int __init kvm_spinlock_debugfs(void)
>>
>>   	d_kvm = kvm_init_debugfs();
>>   	if (d_kvm == NULL)
>> -		return -ENOMEM;
>> +		return -EEXIST;
>
> Why even error out at all here?  You should never care about debugfs
> file creation return values, so why pass any error back up the stack?

We could change this to return 0, but we will still be left with
kvm_main.c: kvm_init_debug() function which creates the kvm  debugfs
directory. (I thought Paolo and Gleb's ack would be needed for
that change since it would be a bigger decision for me)

So I just made the patch to fix only Linus's concern.

But sorry that I did not make that explicit. (infact module insertion 
error was because of successful creation of kvm directory in above code
and then error coming from kvm_init_debug() in kvm_main.c).