On 26.04.24 11:53, Stefan Sperling wrote:
> On Fri, Apr 26, 2024 at 11:12:18AM +0200, Alexander Klimov wrote:
>> Hello everyone!
>>
>> bioctl(8) clearly states that "The RAID 1C discipline
>> requires a minimum of two chunks when a new volume is created".
>>
>> However, bio_createraid() in /usr/src/sbin/bioctl/bioctl.c requires
>> only min_disks = 1; for 1C, allowing me a "bioctl -c 1C -l sdXY softraid0".
>>
>> Luckily the kernel complains with "softraid0: RAID 1C requires two or more chunks".
>>
>> The attached diff lets /sbin/bioctl complain with "bioctl: not enough disks".
>> Ok?
> 
> Not ok, this was done on purpose.
> With your diff there is no way to recover from a broken chunk.

Indeed, bioctl -c also assembles *existing* (detached via -d) RAIDs.
At least 1C ones. Thank you! Was curious how to do that.

But then shouldn't one be able to do that with other disciplines as well?
If one should, shall I create a new patch for this?

> 
>> --- /usr/src/sbin/bioctl/bioctl.c
>> +++ /usr/src/sbin/bioctl/bioctl.c
>> @@ -857,8 +857,10 @@

E.g. RAID 5 here consists of at least 2 chunks when degraded,
but not yet failed, and one more when ok.
But this line demands at least 3 chunks.
I.e. I couldn't assemble a degraded RAID 5 with 2 (3) chunks.

>>   		min_disks = 3;
>>   		break;
>>   	case 'C':
>> -	case 0x1C:
>>   		min_disks = 1;
>> +		break;
>> +	case 0x1C:
>> +		min_disks = 2;
>>   		break;
>>   	case 'c':
>>   		min_disks = 1;
>