Re: [PATCH 2/2] opensm/osm_pkey_mgr.c: In pkey_mgr_update_peer_port, better last block handling

[Hal Rosenstock <hal-LDSdmyG8hGV8YrgS2mwiifqBs+8SCbDb@public.gmane.org>]

Hi Alex,

On 4/7/2011 12:46 PM, Alex Netes wrote:
> Hi Hal,
> 
> On 14:05 Tue 05 Apr     , Hal Rosenstock wrote:
>>
>> PKey table capacities are not required to be multiples of the PKey table block
>> size (32 entries of 16 pkeys).

                        ^^^^^^^
                        16 bit pkeys

>>
>> Current code could enable partition enforcement on the peer switch port
>> even if the last partition table block were truncated. In this case, it's
>> better to disable partition enforcement on those ports.
>>
> 
> What is the motivation for this patch?

The policy question is what to do when that occurs.

> In case where there are more pkeys than sw->switch_info.enforce_cap I guess
> enforcement won't be applied on pkeys > sw->switch_info.enforce_cap.

The SM shouldn't set any such entries in the PKey table per 14.2.5.7
P_KEYTABLE p. 842 line 37:

The AttributeModifier is divided in two halves:
• The least significant 16 bits are a pointer to a block of 32 P_Key
entries to which this Attribute applies.  Valid values are 0 - 2047, and
are further limited by the size of the P_Key table for that node
(specified by the PartitionCap for CAs, routers, and switch management
ports or PartitionEnforcementCap for external ports on switches).

so a conforming SMA should reject such a set.

> This is a user configuration issue. 

Yes.

> Why issue a warning message to a log isn't enough?

That's the minimum that should be done. The question then becomes
whether it's better to enforce for some subset of the partitions or
disable enforrcement. I was trying to avoid another config option for this.

-- Hal

> --Alex

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