Re: [PATCH v2 15/18] hw/block/nvme: reject invalid nsid values in active namespace id list

[Philippe Mathieu-Daudé]

On 7/3/20 10:37 AM, Klaus Jensen wrote:
> On Jul  3 10:20, Philippe Mathieu-Daudé wrote:
>> On 7/3/20 8:34 AM, Klaus Jensen wrote:
>>> From: Klaus Jensen <k.jensen@samsung.com>
>>>
>>> Reject the nsid broadcast value (0xffffffff) and 0xfffffffe in the
>>> Active Namespace ID list.
>>
>> Can we have a definition instead of this 0xfffffffe magic value please?
>>
> 
> Hmm, not really actually. It's not a magic value, its just because the
> logic in Active Namespace ID list would require that it should report
> any namespaces with ids *higher* than the one specified, so since
> 0xffffffff (NVME_NSID_BROADCAST) is invalid, NVME_NSID_BROADCAST - 1
> needs to be as well.

OK.

> 
> What do you say I change it to `min_nsid >= NVME_NSID_BROADCAST - 1`?
> The original condition just reads well if you are sitting with the spec
> on the side.

IMO this is clearer:

  if (min_nsid + 1 >= NVME_NSID_BROADCAST) {
      return NVME_INVALID_NSID | NVME_DNR;
  }

Whichever form you prefer you can amend to the respin patch:
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>

> 
>>>
>>> Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
>>> ---
>>>  hw/block/nvme.c | 4 ++++
>>>  1 file changed, 4 insertions(+)
>>>
>>> diff --git a/hw/block/nvme.c b/hw/block/nvme.c
>>> index 65c2fa3ac1f4..0dac7a41ddae 100644
>>> --- a/hw/block/nvme.c
>>> +++ b/hw/block/nvme.c
>>> @@ -956,6 +956,10 @@ static uint16_t nvme_identify_nslist(NvmeCtrl *n, 
>>> NvmeIdentify *c)
>>>  
>>>      trace_pci_nvme_identify_nslist(min_nsid);
>>>  
>>> +    if (min_nsid == 0xfffffffe || min_nsid == NVME_NSID_BROADCAST) {
>>> +        return NVME_INVALID_NSID | NVME_DNR;
>>> +    }
>>> +
>>>      list = g_malloc0(data_len);
>>>      for (i = 0; i < n->num_namespaces; i++) {
>>>          if (i < min_nsid) {
>>>
>>
>